W&f home improvement

Fire inspectors visit and inspect buildings and other structures, such as sports arenas and shopping malls, to search for fire hazards and to ensure that federal, state, and local fire codes are met. They also test and inspect fire protection and fire extinguishing equipment to ensure that it works. Fire investigators determine the origin and cause of fires by searching the surrounding scene and collecting evidence.

Fire inspectors typically do the following:

• Search for fire hazards
• Ensure that buildings comply with fire codes
• Test fire alarms, sprinklers, and other fire protection and extinguishing equipment
• Inspect equipment such as gasoline storage tanks and air compressors
• Review emergency evacuation plans
• Conduct follow-up visits when an infraction is found
• Confer with developers and planners to review plans for residential and commercial buildings
• Conduct fire and life safety education programs
• Keep detailed records that can be used in a court of law

Fire investigators typically do the following:

• Collect and analyze evidence
• Interview witnesses
• Determine the origin and cause of a fire
• Process and document evidence, such as photographs and diagrams
• Reconstruct the scene of a fire or arson
• Confer with other specialists, such as chemists, engineers, and attorneys, to analyze information
• Send evidence to laboratories to be tested for fingerprints or an accelerant
• Keep detailed records that can be used in a court of law
• Testify in civil and criminal legal proceedings

Unlike fire inspectors, many fire investigators have police powers and carry a weapon.

Forest fire inspectors and prevention specialists assess fire hazards in both public and residential areas. They look for issues that pose a wildfire risk and recommend ways to reduce the fire hazard. During patrols, they ensure that the public is following fire regulations and report fire conditions to central command.

Carpenters construct and repair building frameworks and structures--such as stairways, doorframes, partitions, and rafters--made from wood and other materials. They also may install kitchen cabinets, siding, and drywall.

Carpenters typically do the following:

• Follow blueprints and building plans to meet the needs of clients
• Install structures and fixtures, such as windows and molding
• Measure, cut, or shape wood, plastic, fiberglass, drywall, and other materials
• Construct building frameworks, including wall studs, floor joists, and doorframes
• Help put up, level, and install building framework with the aid of large pulleys and cranes
• Inspect and replace damaged framework or other structures and fixtures
• Instruct and direct laborers and other construction trade helpers

Carpenters are one of the most versatile construction occupations, with workers usually doing a variety of tasks. For example, some carpenters insulate office buildings; others install drywall or kitchen cabinets in homes. Those who help construct large buildings or bridges often make the wooden concrete forms for cement footings or pillars. Some carpenters build braces and scaffolding for buildings.

Carpenters use many different hand and power tools to cut and shape wood, plastic, fiberglass, or drywall. They commonly use handtools, including squares, levels, and chisels, as well as many power tools, such as sanders, circular saws, and nail guns. Carpenters put materials together with nails, screws, staples, and adhesives, and do a final check of their work to ensure accuracy. They use a tape measure on every project because proper measuring increases productivity, reduces waste, and ensures that the pieces being cut are the proper size.

The following are types of carpenters:

Residential carpenters typically specialize in new-home, townhome, and condominium building and remodeling. As part of a single job, they might build and set forms for footings, walls and slabs, and frame and finish exterior walls, roofs, and decks. They frame interior walls, build stairs, and install drywall, crown molding, doors, and kitchen cabinets. Highly-skilled carpenters may also tile floors and lay wood floors and carpet. Fully-trained construction carpenters are easily able to switch from new-home building to remodeling.

Commercial carpenters typically remodel and help build commercial office buildings, hospitals, hotels, schools, and shopping malls. Some specialize in working with light gauge and load-bearing steel framing for interior partitions, exterior framing, and curtain wall construction. Others specialize in working with concrete forming systems and finishing interior and exterior walls, partitions, and ceilings. Highly skilled carpenters can usually do many of the same tasks as residential carpenters.

Industrial carpenters typically work in civil and industrial settings where they put up scaffolding and build and set forms for pouring concrete. Some industrial carpenters build tunnel bracing or partitions in underground passageways and mines to control the circulation of air to worksites. Others build concrete forms for tunnels, bridges, dams, power plants, or sewer construction projects.

Sales managers direct organizations' sales teams. They set sales goals, analyze data, and develop training programs for the organization's sales representatives.

Sales managers typically do the following:

• Oversee regional and local sales managers and their staffs
• Resolve customer complaints regarding sales and service
• Prepare budgets and approve budget expenditures
• Monitor customer preferences to determine the focus of sales efforts
• Analyze sales statistics
• Project sales and determine the profitability of products and services
• Determine discount rates or special pricing plans
• Plan and coordinate training programs for sales staff

Sales managers' responsibilities vary with the size of the organization they work for. However, most sales managers direct the distribution of goods and services by assigning sales territories, setting sales goals, and establishing training programs for the organization's sales representatives.

In some cases, they recruit, hire, and train new members of the sales staff. For more information about sales workers, see the profiles on retail sales workers and wholesale and manufacturing sales representatives.

Sales managers advise sales representatives on ways to improve their sales performance. In large multiproduct organizations, they oversee regional and local sales managers and their staffs.

Sales managers also stay in contact with dealers and distributors. They analyze sales statistics that their staff gathers, both to determine the sales potential and inventory requirements of products and stores and to monitor customers' preferences.

Sales managers work closely with managers from other departments. For example, the marketing department identifies new customers that the sales department can target. The relationship between these two departments is critical to helping an organization expand its client base. Because sales managers monitor customers' preferences and stores' and organizations' inventory needs, they work closely with research and design departments and warehousing departments.

Drywall and ceiling tile installers hang wallboards to walls and ceilings inside buildings. Tapers prepare the wallboards for painting, using tape and other materials. Many workers do both installing and taping.

Drywall installers typically do the following:

• Review design plans to minimize the number of cuts and waste of wallboard
• Measure the location of electrical outlets, plumbing, windows, and vents
• Cut drywall to the right size, using utility knives and power saws
• Fasten drywall panels to interior wall studs, using nails or screws
• Trim and smooth rough edges so boards join evenly

Ceiling tile installers typically do the following:

• Measure according to blueprints or drawings
• Nail or screw supports
• Put tiles or sheets of shock-absorbing materials on ceilings  
• Keep the tile in place with cement adhesive, nails, or screws

Tapers typically do the following:

• Prepare wall surface (wallboard) by patching nail holes
• Apply tape and use sealing compound to cover joints between wallboards
• Apply additional coats of sealing compound to create an even surface
• Sand all joints and holes to a smooth, seamless finish

Installers are also called framers or hangers. Tapers are also called finishers. Ceiling tile installers are sometimes called acoustical carpenters because they work with tiles that block sound.

Once wallboards are hung, workers use increasingly wider trowels to spread multiple coats of spackle over cracks, indentations, and any remaining imperfections. Some workers may use a mechanical applicator, a tool that spreads sealing compound on the wall joint while dispensing and setting tape at the same time.

To work on ceilings, drywall and ceiling tile installers and tapers may use mechanical lifts or stand on stilts, ladders, or scaffolds.

Plumbers, pipefitters, and steamfitters install and repair pipes that carry water, steam, air, or other liquids or gases to and in businesses, homes, and factories.

Plumbers, pipefitters, and steamfitters typically do the following:

• Install pipes and fixtures
• Study blueprints and follow state and local building codes
• Determine the amount of material and type of equipment needed
• Inspect and test installed pipe systems and pipelines
• Troubleshoot and repair systems that are not working
• Replace worn parts

Although plumbers, pipefitters, and steamfitters are three distinct specialties, their duties are often similar. For example, they all install pipes and fittings that carry water, steam, air, or other liquids or gases. They connect pipes, determine the necessary materials for a job, and perform pressure tests to ensure a pipe system is airtight and watertight.

Plumbers, pipefitters, and steamfitters install, maintain, and repair many different types of pipe systems. Some of these systems carry water, dispose of waste, supply gas to ovens, or heat and cool buildings. Other systems, such as those in power plants, carry the steam that powers huge turbines. Pipes also are used in manufacturing plants to move acids, gases, and waste byproducts through the production process.

Master plumbers on construction jobs may be involved with developing blueprints that show where all the pipes and fixtures will go. Their input helps ensure that a structure's plumbing meets building codes, stays within budget, and works well with the location of other features, such as electric wires.

Plumbers and fitters may use many different materials and construction techniques, depending on the type of project. Residential water systems, for example, use copper, steel, and plastic pipe that one or two plumbers can install. Power-plant water systems, by contrast, are made of large steel pipes that usually take a crew of pipefitters to install. Some workers install stainless steel pipes on dairy farms and in factories, mainly to prevent contamination.

Plumbers and fitters sometimes cut holes in walls, ceilings, and floors. With some pipe systems, workers may hang steel supports from ceiling joists to hold the pipe in place. Because pipes are seldom manufactured to the exact size or length, plumbers and fitters measure and then cut and bend lengths of pipe as needed. Their tools include saws, pipe cutters, and pipe-bending machines.

They then connect the pipes, using methods that vary by type of pipe. For example, copper pipe is joined with solder, but steel pipe is often screwed together.

In addition to installation and repair work, journey- and master-level plumbers, pipefitters, and steamfitters often direct apprentices and helpers.

Following are examples of occupational specialties:

Plumbers install and repair water, drainage, and gas pipes in homes, businesses, and factories. They install and repair large water lines, such as those that supply water to buildings, and smaller ones, including ones that supply water to refrigerators. Plumbers also install plumbing fixtures--bathtubs, showers, sinks, and toilets--and appliances such as dishwashers, garbage disposals, and water heaters. They also fix plumbing problems. For example, when a pipe is clogged or leaking, plumbers remove the clog or replace the pipe. Some plumbers maintain septic systems, the large, underground holding tanks that collect waste from houses not connected to a city or county's sewer system.

Pipefitters install and maintain pipes that carry chemicals, acids, and gases. These pipes are mostly in manufacturing, commercial, and industrial settings. They often install and repair pipe systems in power plants, as well as heating and cooling systems in large office buildings. Some pipefitters specialize:

• Gasfitters install pipes that provide clean oxygen to patients in hospitals.
• Sprinklerfitters install and repair fire sprinkler systems in businesses, factories, and residential buildings.
• Steamfitters installpipe systems that move steam under high pressure. Most steamfitters work at campus and natural gas power plants where heat and electricity is generated, but others work in factories that use high-temperature steam pipes.

Woodworkers build a variety of products, such as cabinets and furniture, using wood.

Woodworkers typically do the following:

• Read detailed schematics and blueprints
• Prepare and set up equipment
• Lift wood pieces onto machines, either by hand or with hoists
• Operate wood-making and cutting machines
• Listen for unusual sounds or detect excessive vibration
• Ensure that products meet specifications, making adjustments as necessary
• Use hand tools to trim pieces or assemble products
• Remove and replace dull saw blades

Despite the abundance of plastics, metals, and other materials, wood products continue to be an important part of our daily lives. Woodworkers make wood products, using lumber and synthetic wood materials. Many of these products are mass produced, including most furniture, kitchen cabinets, and musical instruments. Other products are custom made with specialized tools in small shops.

Although the term “woodworker” may evoke the image of a craftsman who builds ornate furniture using hand tools, the modern woodworking trade is highly technical and relies on advanced equipment and highly skilled operators. Workers use automated machinery, such as computerized numerical control (CNC) machines, to do much of the work.

Even specialized artisans generally use a variety of power tools in their work. Much of the work is done in a high-production assembly line facility, but there is also some work that is customized and does not lend itself to being made in an assembly line. Woodworkers are employed in every part of the secondary wood products industry, from sawmill to finished product, and their activities vary.

Woodworkers set up, operate, and tend all types of woodworking machines, such as drill presses, lathes, shapers, routers, sanders, planers, and wood-nailing machines. Operators set up the equipment, cut and shape wooden parts, and verify dimensions, using a template, caliper, and rule. After wood parts are made, woodworkers add fasteners and adhesives and connect the pieces to form a complete unit. They then sand, stain, and, if necessary, coat the wood product with a sealer, such as a lacquer or varnish.

Many of these tasks are handled by different workers with specialized training.

The following are types of woodworkers:

Cabinetmakers and bench carpenters cut, shape, assemble, and make parts for wood products. They often design and create sets of cabinets that are customized for particular spaces. In some cases, their duties begin with designing a set of cabinets to specifications and end with installing them.

Furniture finishers shape, finish, and refinish damaged and worn furniture. They often work with antiques and must judge how to best preserve and repair them. They also do the staining and sealing at the end of the process of making wooden products.

Wood sawing machine setters, operators, and tenders specialize in operating specific pieces of woodworking machinery. They often operate computerized numerical control (CNC) machines.

Woodworking machine setters, operators, and tenders, except sawing, operate woodworking machines, such as drill presses, lathes, routers, sanders, and planers.

Construction and building inspectors ensure that new construction, changes, or repairs comply with local and national building codes and ordinances, zoning regulations, and contract specifications.

Construction and building inspectors typically do the following:

• Review and approve plans that meet building codes, local ordinances, and zoning regulations
• Inspect and monitor construction sites to ensure overall compliance
• Use survey instruments, metering devices, and test equipment to perform inspections
• Monitor installation of plumbing, electrical, and other systems to ensure that the building meets codes
• Verify level, alignment, and elevation of structures and fixtures to ensure building compliance
• Issue violation notices and stop-work orders until building is compliant
• Keep daily logs, including photographs taken during inspection

Construction and building inspectors examine buildings, highways and streets, sewer and water systems, dams, bridges, and other structures. They also inspect electrical; heating, ventilation, air-conditioning, and refrigeration (HVACR); and plumbing systems. Although no two inspections are alike, inspectors do an initial check during the first phase of construction and follow-up inspections throughout the construction project. When the project is finished, they do a final, comprehensive inspection.

The following are types of construction and building inspectors:

Building inspectors check the structural quality and general safety of buildings. Some specialize in structural steel or reinforced-concrete structures, for example.

Electrical inspectors examine the installed electrical systems to ensure they function properly and comply with electrical codes and standards. The inspectors visit worksites to inspect new and existing sound and security systems, wiring, lighting, motors, and generating equipment. They also inspect the installed electrical wiring for HVACR systems and appliances.

Elevator inspectors examine lifting and conveying devices, such as elevators, escalators, moving sidewalks, lifts and hoists, inclined railways, ski lifts, and amusement rides.

Home inspectors typically inspect newly built or previously owned homes, condominiums, townhomes, and other dwellings. Prospective home buyers often hire home inspectors to check and report on a home's structure and overall condition. Sometimes, homeowners hire a home inspector to evaluate their home's condition before placing it on the market.

In addition to examining structural quality, home inspectors examine all home systems and features, including roofing, exterior walls, attached garage or carport, foundation, interior, plumbing, electrical, and HVACR systems. They look for and report violations of building codes, but they do not have the power to enforce compliance with the codes.

Mechanical inspectors examine the installation of HVACR systems and equipment to ensure that they are installed and function properly. They also may inspect commercial kitchen equipment, gas-fired appliances, and boilers.

Plan examiners determine whether the plans for a building or other structure comply with building codes. They also determine whether the structure is suited to the engineering and environmental demands of the building site.

Plumbing inspectors examine the installation of potable water, waste, and vent piping systems to ensure the safety and health of the drinking water system, piping for industrial uses, and the sanitary disposal of waste.

Public works inspectors ensure that federal, state, and local government water and sewer systems, highways, streets, bridges, and dam construction conform to detailed contract specifications. Workers inspect excavation and fill operations, the placement of forms for concrete, concrete mixing and pouring, asphalt paving, and grading operations. Public works inspectors may specialize in highways, structural steel, reinforced concrete, or ditches. Others specialize in dredging operations required for bridges and dams or for harbors.

Specification inspectors ensure that work is performed according to design specifications. Specification inspectors represent the owner's interests, not those of the general public. Insurance companies and financial institutions also may use their services.

A primary concern of building inspectors is fire prevention safety. For more information, see the profile on fire inspectors and investigators.

Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.

Roofers typically do the following:

• Inspect problem roofs to determine the best way to repair them
• Measure roof to calculate the quantities of materials needed
• Replace damaged or rotting joists or plywood
• Install vapor barriers or layers of insulation
• Install shingles, asphalt, metal, or other materials to make the roof watertight
• Align roofing materials with edges of the roof
• Cut roofing materials to fit angles formed by walls, vents, or intersecting roof surfaces
• Cover exposed nail or screw heads with roofing cement or caulk to prevent leakage

Properly installed roofs keep water from leaking into buildings and damaging the interior, equipment, or furnishings.

There are two basic types of roofs, low-slope and steep-slope:

• Low-slope: About two-thirds of all roofs are low-slope. Most commercial, industrial, and apartment buildings have low-slope roofs. Low-slope roofs rise 4 inches or less per horizontal foot and are installed in layers.
  
  For low-slope roofs, roofers typically use several layers of roofing materials or felt membranes stuck together with hot bitumen (a tar-like substance). They glaze the top layer to make a smooth surface or embed gravel in the hot bitumen to make a rough surface.
  
  An increasing number of low-slope roofs are covered with a single-ply membrane of waterproof rubber or thermoplastic compounds.

• Steep-slope: Most of the remaining roofs are steep-slope. Most single-family houses have steep-slope roofs. Steep-slope roofs rise more than 4 inches per horizontal foot.
  
  For steep-slope roofs, roofers typically use asphalt shingles, which often cost less than other coverings. On steep-slope roofs, some roofers also install tile, solar shingles, fiberglass shingles, metal shingles, or shakes (rough wooden shingles).
  
  To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing over the entire roof. Then, starting from the bottom edge, they nail overlapping rows of shingles to the roof.

A small but increasing number of buildings now have “green” roofs that incorporate landscape roofing systems. A landscape roofing system typically begins with a single or multiple waterproof layers. After that layer is proven to be leak free, roofers put a root barrier over it, and, finally, layers of soil, in which vegetation is planted. Roofers must ensure that the roof is watertight and can endure the weight and water needs of the plants.

Painting and coating workers paint and coat a wide range of products, including cars, jewelry, and candy.

Painting and coating workers typically do the following:

• Set up and operate machines that paint or coat products
• Select the paint or coating needed for the job 
• Clean and prepare products to be painted or coated
• Determine the required flow of paint and the quality of the coating 
• Clean and maintain tools and equipment

Millions of items ranging from cars to candy are covered by paint, plastic, varnish, chocolate, or some other type of coating. Painting or coating is used to make a product more attractive or protect it from the elements. The paint finish on an automobile, for example, makes the vehicle more attractive and provides protection from corrosion.

Before workers begin to apply the paint or other coating, they often need to prepare the surface by sanding or cleaning it carefully to prevent dust from becoming trapped under the paint. Sometimes, masking is required, which involves carefully covering portions of the product with tape and paper.

After the product is prepared, workers may use a number of techniques to apply the paint or coating. Perhaps the most straightforward technique is dipping an item in a large vat of paint or some other coating. Spraying products with a solution of paint or another coating is also common. Some factories use automated painting systems.

The following are types of painting and coating workers:

Dippers use power hoists to immerse products in vats of paint, liquid plastic, or other solutions. This technique is commonly used for small parts in electronic equipment, such as cell phones.

Spray machine operators use spray guns to coat metal, wood, ceramic, fabric, paper, and food products with paint and other coating solutions.

Coating, painting, and spraying machine setters, operators, and tenders position the spray guns, set the nozzles, and synchronize the action of the guns with the speed of the conveyor carrying products through the machine and through drying ovens. During the operation of the painting machines, these workers tend the equipment, watch gauges on the control panel, and check products to ensure that they are being painted evenly. The operator may use a manual spray gun to “touch up” flaws.

Painting, coating, and decorating workers paint, coat, or decorate products such as furniture, glass, pottery, toys, cakes, and books. Some workers coat confectionery, bakery, and other food products with melted chocolate, cheese, oils, sugar, or other substances. Paper is often coated to give it its gloss. Silver, tin, and copper solutions are frequently sprayed on glass to make mirrors.

Transportation equipment painters are the best known group of painting and coating workers. There are three major specialties:

<p style=" margin-left: 20.0px;">Transportation equipment workers who refinish old or damaged cars, trucks, and buses in automotive body repair and paint shops normally apply paint by hand with a controlled spray gun. Those who work in repair shops are among the most highly skilled manual spray operators: They perform intricate, detailed work and mix paints to match the original color, a task that is especially difficult if the color has faded. Preparing an old car is similar to painting other metal objects.

<p style=" margin-left: 20.0px;">Transportation equipment painters who work on new cars oversee several automated steps. A modern car is first dipped in an anticorrosion bath, coated with colored paint, and then painted in several coats of clear paint to prevent damage to the colored paint.

<p style=" margin-left: 20.0px;">Other transportation equipment painters either paint equipment too large to paint automatically--such as ships or giant construction equipment--or do touchup work to fix flaws in the paint caused by damage either during assembly or during the automated painting process.

Construction laborers and helpers do many basic tasks that require physical labor on construction sites.

Construction laborers and helpers typically do the following:

• Clean and prepare construction sites by removing debris and possible hazards
• Load or unload building materials to be used in construction
• Build or take apart bracing, barricades, forms (molds that determine the shape of concrete), scaffolding, and temporary structures
• Dig trenches, backfill holes, or compact earth to prepare for construction
• Operate or tend equipment and machines used in construction, such as concrete mixers
• Help other craftworkers with their duties
• Follow construction plans and instructions from the people they are working for

Construction laborers and helpers work on almost all construction sites, doing a wide range of tasks from the very easy to the extremely difficult and hazardous. Although many of the tasks they do require some training and experience, most jobs usually require little skill and can be learned quickly. 

The following are occupational specialties:

Construction laborers do a variety of construction-related activities during all phases of construction. Although most laborers are generalists--such as those who install barricades, cones, and markers to control traffic patterns--many others specialize. For example, those who operate the machines and equipment that lay concrete or asphalt on roads are more likely to specialize in those areas.

Most construction laborers work in the following areas:

• Building homes and businesses
• Tearing down buildings
• Removing hazardous materials
• Building highways and roads
• Digging tunnels and mine shafts

Construction laborers use a variety of tools and equipment. Some tools are simple, such as brooms and shovels; other equipment is more sophisticated, such as pavement breakers, jackhammers, earth tampers, and surveying equipment.

With special training, laborers may help transport and use explosives or run hydraulic boring machines to dig out tunnels. They may learn to use laser beam equipment to place pipes and use computers to control robotic pipe cutters. They may become certified to remove asbestos, lead, or chemicals.

Helpers assist construction craftworkers, such as electricians and carpenters, with a variety of basic tasks. They may carry tools and materials or help set up equipment. For example, many helpers work with cement masons to move and set forms. Many other helpers assist with taking apart equipment, cleaning up sites, and disposing of waste, as well as helping with any other needs of craftworkers.

Many construction trades have helpers who assist craftworkers. The following are examples of trades that have associated helpers:

• Brickmasons, blockmasons, stonemasons, and tile and marble setters
• Carpenters
• Electricians
• Painters, paperhangers, plasterers, and stucco masons
• Pipelayers, plumbers, pipefitters, and steamfitters
• Roofers

Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.

Roofers typically do the following:

• Inspect problem roofs to determine the best way to repair them
• Measure roof to calculate the quantities of materials needed
• Replace damaged or rotting joists or plywood
• Install vapor barriers or layers of insulation
• Install shingles, asphalt, metal, or other materials to make the roof watertight
• Align roofing materials with edges of the roof
• Cut roofing materials to fit angles formed by walls, vents, or intersecting roof surfaces
• Cover exposed nail or screw heads with roofing cement or caulk to prevent leakage

Properly installed roofs keep water from leaking into buildings and damaging the interior, equipment, or furnishings.

There are two basic types of roofs, low-slope and steep-slope:

• Low-slope: About two-thirds of all roofs are low-slope. Most commercial, industrial, and apartment buildings have low-slope roofs. Low-slope roofs rise 4 inches or less per horizontal foot and are installed in layers.
  
  For low-slope roofs, roofers typically use several layers of roofing materials or felt membranes stuck together with hot bitumen (a tar-like substance). They glaze the top layer to make a smooth surface or embed gravel in the hot bitumen to make a rough surface.
  
  An increasing number of low-slope roofs are covered with a single-ply membrane of waterproof rubber or thermoplastic compounds.

• Steep-slope: Most of the remaining roofs are steep-slope. Most single-family houses have steep-slope roofs. Steep-slope roofs rise more than 4 inches per horizontal foot.
  
  For steep-slope roofs, roofers typically use asphalt shingles, which often cost less than other coverings. On steep-slope roofs, some roofers also install tile, solar shingles, fiberglass shingles, metal shingles, or shakes (rough wooden shingles).
  
  To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing over the entire roof. Then, starting from the bottom edge, they nail overlapping rows of shingles to the roof.

A small but increasing number of buildings now have “green” roofs that incorporate landscape roofing systems. A landscape roofing system typically begins with a single or multiple waterproof layers. After that layer is proven to be leak free, roofers put a root barrier over it, and, finally, layers of soil, in which vegetation is planted. Roofers must ensure that the roof is watertight and can endure the weight and water needs of the plants.

Construction laborers and helpers do many basic tasks that require physical labor on construction sites.

Construction laborers and helpers typically do the following:

• Clean and prepare construction sites by removing debris and possible hazards
• Load or unload building materials to be used in construction
• Build or take apart bracing, barricades, forms (molds that determine the shape of concrete), scaffolding, and temporary structures
• Dig trenches, backfill holes, or compact earth to prepare for construction
• Operate or tend equipment and machines used in construction, such as concrete mixers
• Help other craftworkers with their duties
• Follow construction plans and instructions from the people they are working for

Construction laborers and helpers work on almost all construction sites, doing a wide range of tasks from the very easy to the extremely difficult and hazardous. Although many of the tasks they do require some training and experience, most jobs usually require little skill and can be learned quickly. 

The following are occupational specialties:

Construction laborers do a variety of construction-related activities during all phases of construction. Although most laborers are generalists--such as those who install barricades, cones, and markers to control traffic patterns--many others specialize. For example, those who operate the machines and equipment that lay concrete or asphalt on roads are more likely to specialize in those areas.

Most construction laborers work in the following areas:

• Building homes and businesses
• Tearing down buildings
• Removing hazardous materials
• Building highways and roads
• Digging tunnels and mine shafts

Construction laborers use a variety of tools and equipment. Some tools are simple, such as brooms and shovels; other equipment is more sophisticated, such as pavement breakers, jackhammers, earth tampers, and surveying equipment.

With special training, laborers may help transport and use explosives or run hydraulic boring machines to dig out tunnels. They may learn to use laser beam equipment to place pipes and use computers to control robotic pipe cutters. They may become certified to remove asbestos, lead, or chemicals.

Helpers assist construction craftworkers, such as electricians and carpenters, with a variety of basic tasks. They may carry tools and materials or help set up equipment. For example, many helpers work with cement masons to move and set forms. Many other helpers assist with taking apart equipment, cleaning up sites, and disposing of waste, as well as helping with any other needs of craftworkers.

Many construction trades have helpers who assist craftworkers. The following are examples of trades that have associated helpers:

• Brickmasons, blockmasons, stonemasons, and tile and marble setters
• Carpenters
• Electricians
• Painters, paperhangers, plasterers, and stucco masons
• Pipelayers, plumbers, pipefitters, and steamfitters
• Roofers

Cost estimators collect and analyze data to estimate the time, money, resources, and labor required for product manufacturing, construction projects, or services. Some specialize in a particular industry or product type.

Cost estimators typically do the following:

• Consult with industry experts to discuss estimates and resolve issues
• Identify and quantify cost factors, such as production time and raw material, equipment, and labor expenses
• Travel to job sites to gather information on materials needed, labor requirements, and other factors 
• Read blueprints and technical documents to prepare estimates
• Collaborate with engineers, architects, owners, and contractors on estimates
• Use sophisticated computer software to calculate estimates 
• Evaluate a product's cost effectiveness or profitability
• Recommend ways to make a product more cost effective or profitable
• Prepare estimates for clients and other business managers
• Develop project plans for the duration of the project

Accurately predicting the cost, size, and duration of future construction and manufacturing projects is vital to the survival of any business. Cost estimators' calculations give managers or investors this information.

When making calculations, estimators analyze many inputs to determine how much time, money, and labor a project needs, or how profitable it will be. These estimates have to take many factors into account, including allowances for wasted material, bad weather, shipping delays, and other factors that can increase costs and lower profitability.

Cost estimators use sophisticated computer software, including database, simulation, and complex mathematical programs. Cost estimators often use a computer database with information on the costs of other similar projects.

General contractors usually hire cost estimators for specific parts of a large construction project, such as estimating the electrical work or the excavation phase. In such cases, the estimator calculates the cost of the construction phase for which the contractor is responsible, rather than calculating the cost of the entire project. The general contractor usually also has a cost estimator who calculates the total project cost by analyzing the bids that the subcontractors' cost estimators prepared.

Some estimators are hired by manufacturers to analyze certain products or processes.

The following are the two primary types of cost estimators:

Construction cost estimators estimate construction work. More than half of all cost estimators work in the construction industry. They may, for example, estimate the total cost of building a bridge or a highway. They may identify direct costs, such as raw materials and labor requirements, and set a timeline for the project. Although many work directly for construction firms, some work for contractors, architects, and engineering firms.

Manufacturing cost estimators calculate the costs of developing, producing, or redesigning a company's goods and services. For example, a cost estimator working for a home appliance manufacturer may determine whether a new type of dishwasher will be profitable to manufacture.

Some manufacturing cost estimators work in software development. Many high-technology products require a considerable amount of computer programming, and the costs of software development are difficult to calculate.  

Two other groups also sometimes do cost estimating in their jobs. Operations research, production control, cost, and price analysts who work for government agencies may do significant amounts of cost estimating in the course of their usual duties. Construction managers also may spend considerable time estimating costs. For more information, see the profiles on operations research analysts and construction managers.

Cement masons pour, smooth, and finish concrete floors, sidewalks, roads, and curbs. Using a cement mixture, terrazzo workers create durable and decorative surfaces for floors and stairways.

Cement masons typically do the following:

• Set the forms that hold concrete in place
• Install reinforcing rebar or mesh wire to strengthen the concrete
• Signal truck drivers to facilitate the pouring of concrete
• Spread, level, and smooth concrete, using a trowel, float, or screed
• Mold expansion joints and edges
• Monitor curing (hardening) to ensure a durable, smooth, and uniform finish
• Apply sealants or waterproofing to protect concrete

Terrazzo workers typically do the following (in addition to what cement masons do):

• Measure ingredients for terrazzo
• Blend a marble chip mixture that may have colors in it 
• Grind and polish surfaces for a smooth, lustrous look

Concrete is one of the most common and durable materials used in construction. Once set, concrete--a mixture of cement, sand, gravel, and water--becomes the foundation for everything from decorative patios and floors to huge dams or miles of roadways.

The following are types of cement masons and terrazzo workers:

Cement masons and concrete finishers place and finish concrete. They may color concrete surfaces, expose aggregate (small stones) in walls and sidewalks, or make concrete beams, columns, and panels.

Throughout the process of pouring, leveling, and finishing concrete, cement masons must monitor how the wind, heat, or cold affects the curing of the concrete. They must have a thorough knowledge of the characteristics of concrete so that, by using sight and touch, they can determine what is happening to the concrete and take measures to prevent defects.

Terrazzo workers and finishers create decorative walkways, floors, patios, and panels. Although much of the preliminary work in pouring, leveling, and finishing concrete is similar to that of cement masons, terrazzo workers create more decorative finishes by blending a fine marble chip into the cement, which is often colored. Once the terrazzo is thoroughly set, workers correct any depressions or imperfections with a grinder to create a smooth, uniform finish.

Carpenters construct and repair building frameworks and structures--such as stairways, doorframes, partitions, and rafters--made from wood and other materials. They also may install kitchen cabinets, siding, and drywall.

Carpenters typically do the following:

• Follow blueprints and building plans to meet the needs of clients
• Install structures and fixtures, such as windows and molding
• Measure, cut, or shape wood, plastic, fiberglass, drywall, and other materials
• Construct building frameworks, including wall studs, floor joists, and doorframes
• Help put up, level, and install building framework with the aid of large pulleys and cranes
• Inspect and replace damaged framework or other structures and fixtures
• Instruct and direct laborers and other construction trade helpers

Carpenters are one of the most versatile construction occupations, with workers usually doing a variety of tasks. For example, some carpenters insulate office buildings; others install drywall or kitchen cabinets in homes. Those who help construct large buildings or bridges often make the wooden concrete forms for cement footings or pillars. Some carpenters build braces and scaffolding for buildings.

Carpenters use many different hand and power tools to cut and shape wood, plastic, fiberglass, or drywall. They commonly use handtools, including squares, levels, and chisels, as well as many power tools, such as sanders, circular saws, and nail guns. Carpenters put materials together with nails, screws, staples, and adhesives, and do a final check of their work to ensure accuracy. They use a tape measure on every project because proper measuring increases productivity, reduces waste, and ensures that the pieces being cut are the proper size.

The following are types of carpenters:

Residential carpenters typically specialize in new-home, townhome, and condominium building and remodeling. As part of a single job, they might build and set forms for footings, walls and slabs, and frame and finish exterior walls, roofs, and decks. They frame interior walls, build stairs, and install drywall, crown molding, doors, and kitchen cabinets. Highly-skilled carpenters may also tile floors and lay wood floors and carpet. Fully-trained construction carpenters are easily able to switch from new-home building to remodeling.

Commercial carpenters typically remodel and help build commercial office buildings, hospitals, hotels, schools, and shopping malls. Some specialize in working with light gauge and load-bearing steel framing for interior partitions, exterior framing, and curtain wall construction. Others specialize in working with concrete forming systems and finishing interior and exterior walls, partitions, and ceilings. Highly skilled carpenters can usually do many of the same tasks as residential carpenters.

Industrial carpenters typically work in civil and industrial settings where they put up scaffolding and build and set forms for pouring concrete. Some industrial carpenters build tunnel bracing or partitions in underground passageways and mines to control the circulation of air to worksites. Others build concrete forms for tunnels, bridges, dams, power plants, or sewer construction projects.

Painters apply paint, stain, and coatings to walls, buildings, bridges, and other structures.

Painters typically do the following:

• Cover floors and furniture with drop-cloths and tarps to protect surfaces
• Remove fixtures such as pictures, door knobs, or electric switch covers
• Put up scaffolding and set up ladders
• Fill holes and cracks with caulk, putty, plaster, or other compounds
• Prepare surfaces by scraping, wire brushing, or sanding to a smooth finish
• Calculate the area to be painted and the amount of paint needed
• Apply primers or sealers so the paint will adhere
• Choose and mix paints and stains to reach desired color and appearance
• Apply paint or other finishes using hand brushes, rollers, or sprayers

Applying paint to interior walls makes surfaces attractive and vibrant. In addition, paints and other sealers protect exterior surfaces from erosion caused by exposure to the weather.

Because there are several ways to apply paint, workers must be able to choose the proper tool for each job, such as the correct roller, power sprayer, and the right size brush. Choosing the right tool typically depends on the surface to be covered and the characteristics of the finish.

A few painters--mainly industrial--must use special safety equipment. For example, painting in confined spaces such as the inside of a large storage tank, requires workers to wear self-contained suits to avoid inhaling toxic fumes. When painting bridges, tall buildings, or oil rigs, painters may work from scaffolding, bosun's chairs, and harnesses to reach work areas.

The following are examples of types of painters:  

Construction painters apply paints, stains, and coatings to interior and exterior walls, new buildings, and other structural surfaces.

Maintenance painters remove old finishes and apply paints, stains, and coatings later in a structure's life. Some painters specialize in painting or coating industrial structures, such as bridges and oil rigs, to prevent corrosion.

Artisan painters specialize in creating distinct finishes by using one of many decorative techniques. One technique is adding glaze for added depth and texture. Other common techniques may include sponging, distressing, rag-rolling, color blocking, and faux finishes. 

Painting and coating workers apply materials to manufactured products, such as furniture, toys and pottery, as well as transportation equipment including trucks, buses, boats, and airplanes. For more information about these painters, see the profile on painting and coating workers.

Architects plan and design buildings and other structures.

Architects typically do the following:

• Seek new work by marketing and giving presentations
• Consult with clients to determine requirements for structures
• Estimate materials, equipment, costs, and construction time
• Prepare, design, and structure specifications
• Direct workers who prepare drawings and documents
• Prepare scaled drawings of the project
• Prepare contract documents for building contractors
• Manage construction contracts
• Visit worksites to ensure that construction adheres to architectural plans

People need places to live, work, play, learn, worship, meet, govern, shop, and eat. Architects are responsible for designing these places, whether they are private or public; indoors or outdoors; or rooms, buildings, or complexes.

Architects discuss with clients the objectives, requirements, and budget of a project. In some cases, architects provide various predesign services, such as feasibility and environmental impact studies, site selection, cost analyses and land-use studies, and design requirements. For example, architects may determine a building's space requirements by researching its number and types of potential users.

After discussing and agreeing on the initial proposal, architects develop final construction plans that show the building's appearance and details for its construction. Accompanying these plans are drawings of the structural system; air-conditioning, heating, and ventilating systems; electrical systems; communications systems; plumbing; and, possibly, site and landscape plans.

In developing designs, architects must follow building codes, zoning laws, fire regulations, and other ordinances, such as those requiring easy access by people who are disabled.

Computer-aided design and drafting (CADD) and building information modeling (BIM) technology have replaced traditional drafting paper and pencil as the most common methods for creating designs and construction drawings.

Architects also may help clients get construction bids, select contractors, and negotiate construction contracts.

As construction proceeds, architects may visit building sites to ensure that contractors follow the design, keep to the schedule, use the specified materials, and meet work-quality standards. The job is not complete until all construction is finished, required tests are conducted, and construction costs are paid.

Architects often work with workers in related professions. For more information on these occupations, see the profiles on civil engineers, urban and regional planners, interior designers, and landscape architects.

Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.

Roofers typically do the following:

• Inspect problem roofs to determine the best way to repair them
• Measure roof to calculate the quantities of materials needed
• Replace damaged or rotting joists or plywood
• Install vapor barriers or layers of insulation
• Install shingles, asphalt, metal, or other materials to make the roof watertight
• Align roofing materials with edges of the roof
• Cut roofing materials to fit angles formed by walls, vents, or intersecting roof surfaces
• Cover exposed nail or screw heads with roofing cement or caulk to prevent leakage

Properly installed roofs keep water from leaking into buildings and damaging the interior, equipment, or furnishings.

There are two basic types of roofs, low-slope and steep-slope:

• Low-slope: About two-thirds of all roofs are low-slope. Most commercial, industrial, and apartment buildings have low-slope roofs. Low-slope roofs rise 4 inches or less per horizontal foot and are installed in layers.
  
  For low-slope roofs, roofers typically use several layers of roofing materials or felt membranes stuck together with hot bitumen (a tar-like substance). They glaze the top layer to make a smooth surface or embed gravel in the hot bitumen to make a rough surface.
  
  An increasing number of low-slope roofs are covered with a single-ply membrane of waterproof rubber or thermoplastic compounds.

• Steep-slope: Most of the remaining roofs are steep-slope. Most single-family houses have steep-slope roofs. Steep-slope roofs rise more than 4 inches per horizontal foot.
  
  For steep-slope roofs, roofers typically use asphalt shingles, which often cost less than other coverings. On steep-slope roofs, some roofers also install tile, solar shingles, fiberglass shingles, metal shingles, or shakes (rough wooden shingles).
  
  To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing over the entire roof. Then, starting from the bottom edge, they nail overlapping rows of shingles to the roof.

A small but increasing number of buildings now have “green” roofs that incorporate landscape roofing systems. A landscape roofing system typically begins with a single or multiple waterproof layers. After that layer is proven to be leak free, roofers put a root barrier over it, and, finally, layers of soil, in which vegetation is planted. Roofers must ensure that the roof is watertight and can endure the weight and water needs of the plants.

Carpenters construct and repair building frameworks and structures--such as stairways, doorframes, partitions, and rafters--made from wood and other materials. They also may install kitchen cabinets, siding, and drywall.

Carpenters typically do the following:

• Follow blueprints and building plans to meet the needs of clients
• Install structures and fixtures, such as windows and molding
• Measure, cut, or shape wood, plastic, fiberglass, drywall, and other materials
• Construct building frameworks, including wall studs, floor joists, and doorframes
• Help put up, level, and install building framework with the aid of large pulleys and cranes
• Inspect and replace damaged framework or other structures and fixtures
• Instruct and direct laborers and other construction trade helpers

Carpenters are one of the most versatile construction occupations, with workers usually doing a variety of tasks. For example, some carpenters insulate office buildings; others install drywall or kitchen cabinets in homes. Those who help construct large buildings or bridges often make the wooden concrete forms for cement footings or pillars. Some carpenters build braces and scaffolding for buildings.

Carpenters use many different hand and power tools to cut and shape wood, plastic, fiberglass, or drywall. They commonly use handtools, including squares, levels, and chisels, as well as many power tools, such as sanders, circular saws, and nail guns. Carpenters put materials together with nails, screws, staples, and adhesives, and do a final check of their work to ensure accuracy. They use a tape measure on every project because proper measuring increases productivity, reduces waste, and ensures that the pieces being cut are the proper size.

The following are types of carpenters:

Residential carpenters typically specialize in new-home, townhome, and condominium building and remodeling. As part of a single job, they might build and set forms for footings, walls and slabs, and frame and finish exterior walls, roofs, and decks. They frame interior walls, build stairs, and install drywall, crown molding, doors, and kitchen cabinets. Highly-skilled carpenters may also tile floors and lay wood floors and carpet. Fully-trained construction carpenters are easily able to switch from new-home building to remodeling.

Commercial carpenters typically remodel and help build commercial office buildings, hospitals, hotels, schools, and shopping malls. Some specialize in working with light gauge and load-bearing steel framing for interior partitions, exterior framing, and curtain wall construction. Others specialize in working with concrete forming systems and finishing interior and exterior walls, partitions, and ceilings. Highly skilled carpenters can usually do many of the same tasks as residential carpenters.

Industrial carpenters typically work in civil and industrial settings where they put up scaffolding and build and set forms for pouring concrete. Some industrial carpenters build tunnel bracing or partitions in underground passageways and mines to control the circulation of air to worksites. Others build concrete forms for tunnels, bridges, dams, power plants, or sewer construction projects.

Health and safety engineers develop procedures and design systems to keep people from getting sick or injured and to keep property from being damaged. They combine a knowledge of health or safety and of systems engineering to make sure that chemicals, machinery, software, furniture, and other products are not going to cause harm to people or buildings.

Health and safety engineers typically do the following:

• Review plans and specifications for new machinery or equipment to make sure it meets safety requirements
• Inspect facilities, machinery, and safety equipment to identify and correct potential hazards
• Evaluate the effectiveness of various industrial control mechanisms
• Ensure that a building or product complies with health and safety regulations, especially after an inspection that required changes
• Install safety devices on machinery or direct the installation of these devices
• Review employee safety programs and recommend improvements
• Maintain and apply their knowledge of current policies, regulations, and industrial processes

Health and safety engineers also investigate industrial accidents, injuries, or occupational diseases to determine their causes and to see whether they could have been or can be prevented. They interview employers and employees to learn about work environments and incidents leading up to accidents or injuries. They also evaluate the corrections that were made to remedy violations found during health inspections.

Health and safety engineers are also active in two related fields: industrial hygiene and occupational hygiene. 

In industrial hygiene, they focus on the effects of chemical, physical, and biological agents. They recognize, evaluate, and control these agents to keep people from getting sick or injured. For example, they might anticipate that a particular manufacturing process will give off a potentially harmful chemical and recommend either a change to the process or a way to contain and control the chemical.  

In occupational hygiene, health and safety engineers investigate the environment in which people work and use science and engineering to recommend changes to keep workers from being exposed to sickness or injuries. They help employers and employees understand the risks and improve working conditions and working practices. For example, they might observe that the noise level in a factory is likely to cause short-term and long-term harm to workers and recommend ways to reduce the noise level through changes to the building or by having workers wear strong headphones.

Health and safety engineering is a broad field covering many activities. The following are specific types of health and safety engineers:

Aerospace safety engineers work on missiles, radars, and satellites to make sure that they function safely as designed.

Fire prevention and protection engineers design fire prevention systems for all kinds of buildings. They often work for architects during the design phase of new buildings or renovations. They must be licensed, and they must keep up with changes in fire codes and regulations.

Product safety engineers investigate the causes of accidents or injuries that might have resulted from the use or misuse of a product. They propose solutions to reduce or eliminate any safety issues associated with products. They also participate in the design phase of new products to prevent injuries, illnesses, or property damage that could occur with the use of the product.

Systems safety engineers work in many fields, including aerospace, and are moving into new fields, such as software safety, medical safety, and environmental safety. These engineers take a systemic approach to identify hazards in these new fields so that accidents and injuries can be avoided.

For information on health and safety engineers who work in mines, see the profile on mining and geological engineers.

Construction and building inspectors ensure that new construction, changes, or repairs comply with local and national building codes and ordinances, zoning regulations, and contract specifications.

Construction and building inspectors typically do the following:

• Review and approve plans that meet building codes, local ordinances, and zoning regulations
• Inspect and monitor construction sites to ensure overall compliance
• Use survey instruments, metering devices, and test equipment to perform inspections
• Monitor installation of plumbing, electrical, and other systems to ensure that the building meets codes
• Verify level, alignment, and elevation of structures and fixtures to ensure building compliance
• Issue violation notices and stop-work orders until building is compliant
• Keep daily logs, including photographs taken during inspection

Construction and building inspectors examine buildings, highways and streets, sewer and water systems, dams, bridges, and other structures. They also inspect electrical; heating, ventilation, air-conditioning, and refrigeration (HVACR); and plumbing systems. Although no two inspections are alike, inspectors do an initial check during the first phase of construction and follow-up inspections throughout the construction project. When the project is finished, they do a final, comprehensive inspection.

The following are types of construction and building inspectors:

Building inspectors check the structural quality and general safety of buildings. Some specialize in structural steel or reinforced-concrete structures, for example.

Electrical inspectors examine the installed electrical systems to ensure they function properly and comply with electrical codes and standards. The inspectors visit worksites to inspect new and existing sound and security systems, wiring, lighting, motors, and generating equipment. They also inspect the installed electrical wiring for HVACR systems and appliances.

Elevator inspectors examine lifting and conveying devices, such as elevators, escalators, moving sidewalks, lifts and hoists, inclined railways, ski lifts, and amusement rides.

Home inspectors typically inspect newly built or previously owned homes, condominiums, townhomes, and other dwellings. Prospective home buyers often hire home inspectors to check and report on a home's structure and overall condition. Sometimes, homeowners hire a home inspector to evaluate their home's condition before placing it on the market.

In addition to examining structural quality, home inspectors examine all home systems and features, including roofing, exterior walls, attached garage or carport, foundation, interior, plumbing, electrical, and HVACR systems. They look for and report violations of building codes, but they do not have the power to enforce compliance with the codes.

Mechanical inspectors examine the installation of HVACR systems and equipment to ensure that they are installed and function properly. They also may inspect commercial kitchen equipment, gas-fired appliances, and boilers.

Plan examiners determine whether the plans for a building or other structure comply with building codes. They also determine whether the structure is suited to the engineering and environmental demands of the building site.

Plumbing inspectors examine the installation of potable water, waste, and vent piping systems to ensure the safety and health of the drinking water system, piping for industrial uses, and the sanitary disposal of waste.

Public works inspectors ensure that federal, state, and local government water and sewer systems, highways, streets, bridges, and dam construction conform to detailed contract specifications. Workers inspect excavation and fill operations, the placement of forms for concrete, concrete mixing and pouring, asphalt paving, and grading operations. Public works inspectors may specialize in highways, structural steel, reinforced concrete, or ditches. Others specialize in dredging operations required for bridges and dams or for harbors.

Specification inspectors ensure that work is performed according to design specifications. Specification inspectors represent the owner's interests, not those of the general public. Insurance companies and financial institutions also may use their services.

A primary concern of building inspectors is fire prevention safety. For more information, see the profile on fire inspectors and investigators.

Brickmasons, blockmasons, and stonemasons (or, simply, masons) use bricks, concrete blocks, and natural stones to build fences, walkways, walls, and other structures.

Masons typically do the following:

• Read blueprints or drawings to calculate materials needed
• Lay out patterns or foundations, using a straightedge
• Break or cut bricks, stones, or blocks to their appropriate size
• Mix mortar or grout and spread it onto a slab or foundation
• Lay bricks, blocks, or stones according to plans
• Clean excess mortar with trowels and other handtools
• Construct corners with a corner pole or by building a corner pyramid
• Ensure that a structure is perfectly vertical and horizontal, using a plumb bob and level
• Clean and polish surfaces with hand or power tools
• Fill expansion and contraction joints with the appropriate caulking materials

The following are common types of masons:

Brickmasons and blockmasons--who often are called bricklayers--build and repair walls, floors, partitions, fireplaces, chimneys, and other structures with brick, precast masonry panels, concrete block, and other masonry materials.

Pointing, cleaning, and caulking workers repair brickwork, particularly on older structures on which mortar has come loose. Special care must be taken not to damage the structural integrity or the existing bricks.

Refractory masons are brickmasons who specialize in installing firebrick and refractory tile in high-temperature boilers, furnaces, cupolas, ladles, and soaking pits in industrial establishments. Most of these workers are employed in steel mills, where molten materials flow on refractory beds from furnaces to rolling machines. They also are employed at oil refineries, glass furnaces, incinerators, and other locations with manufacturing processes that require high temperatures.

Stonemasons build stone walls, as well as set stone exteriors and floors. They work with two types of stone: natural-cut stone, such as marble, granite, and limestone; and artificial stone, made from concrete, marble chips, or other masonry materials. Using a special hammer or a diamond-blade saw, workers cut stone to make various shapes and sizes. Some stonemasons specialize in setting marble, which is similar to setting large pieces of stone.

Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.

Roofers typically do the following:

• Inspect problem roofs to determine the best way to repair them
• Measure roof to calculate the quantities of materials needed
• Replace damaged or rotting joists or plywood
• Install vapor barriers or layers of insulation
• Install shingles, asphalt, metal, or other materials to make the roof watertight
• Align roofing materials with edges of the roof
• Cut roofing materials to fit angles formed by walls, vents, or intersecting roof surfaces
• Cover exposed nail or screw heads with roofing cement or caulk to prevent leakage

Properly installed roofs keep water from leaking into buildings and damaging the interior, equipment, or furnishings.

There are two basic types of roofs, low-slope and steep-slope:

• Low-slope: About two-thirds of all roofs are low-slope. Most commercial, industrial, and apartment buildings have low-slope roofs. Low-slope roofs rise 4 inches or less per horizontal foot and are installed in layers.
  
  For low-slope roofs, roofers typically use several layers of roofing materials or felt membranes stuck together with hot bitumen (a tar-like substance). They glaze the top layer to make a smooth surface or embed gravel in the hot bitumen to make a rough surface.
  
  An increasing number of low-slope roofs are covered with a single-ply membrane of waterproof rubber or thermoplastic compounds.

• Steep-slope: Most of the remaining roofs are steep-slope. Most single-family houses have steep-slope roofs. Steep-slope roofs rise more than 4 inches per horizontal foot.
  
  For steep-slope roofs, roofers typically use asphalt shingles, which often cost less than other coverings. On steep-slope roofs, some roofers also install tile, solar shingles, fiberglass shingles, metal shingles, or shakes (rough wooden shingles).
  
  To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing over the entire roof. Then, starting from the bottom edge, they nail overlapping rows of shingles to the roof.

A small but increasing number of buildings now have “green” roofs that incorporate landscape roofing systems. A landscape roofing system typically begins with a single or multiple waterproof layers. After that layer is proven to be leak free, roofers put a root barrier over it, and, finally, layers of soil, in which vegetation is planted. Roofers must ensure that the roof is watertight and can endure the weight and water needs of the plants.

Construction managers plan, coordinate, budget, and supervise construction projects from early development to completion.

Construction managers typically do the following:

• Prepare and negotiate cost estimates, budgets, and work timetables
• Select appropriate construction methods and strategies
• Interpret and explain contracts and technical information to workers and other professionals
• Report on work progress and budget matters to clients
• Collaborate with architects, engineers, and other construction and building specialists
• Instruct and supervise construction personnel and activities onsite
• Respond to work delays and other problems and emergencies
• Select, hire, and instruct laborers and subcontractors  
• Comply with legal requirements, building and safety codes, and other regulations

Construction managers, often called general contractors or project managers, coordinate and supervise a wide variety of projects, including the building of all types of residential, commercial, and industrial structures, roads, bridges, powerplants, schools, and hospitals. They oversee specialized contractors and other personnel. Construction managers schedule and coordinate all design and construction processes to ensure a productive and safe work environment. They also make sure jobs are completed on time and on budget with the right amount of tools, equipment, and materials. Many managers also are responsible for obtaining necessary permits and licenses. They are often responsible for multiple projects at a time.

Construction managers work closely with other building specialists, such as architects, engineers, and a variety of trade workers, such as stonemasons, electricians, and carpenters. Projects may require specialists in everything from structural metalworking and painting, to landscaping, building roads, installing carpets, and excavating sites. Depending on the project, construction managers also may interact with lawyers and local government officials. For example, when working on city-owned property or municipal buildings, managers sometimes confer with city council members to ensure that all regulations are met.

For projects too large to be managed by one person, such as office buildings and industrial complexes, a construction manager would only be in charge of one part of the project. Each construction manager would oversee a specific construction phase and choose subcontractors to complete it. Construction managers may need to collaborate and coordinate with other construction managers who are responsible for different aspects of the project.

To maximize efficiency and productivity, construction managers often use specialized cost-estimating and planning software to effectively budget the time and money required to complete specific projects. Many managers also use software to determine the best way to get materials to the building site. For more information, see the profile on cost estimators.

Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.

Roofers typically do the following:

• Inspect problem roofs to determine the best way to repair them
• Measure roof to calculate the quantities of materials needed
• Replace damaged or rotting joists or plywood
• Install vapor barriers or layers of insulation
• Install shingles, asphalt, metal, or other materials to make the roof watertight
• Align roofing materials with edges of the roof
• Cut roofing materials to fit angles formed by walls, vents, or intersecting roof surfaces
• Cover exposed nail or screw heads with roofing cement or caulk to prevent leakage

Properly installed roofs keep water from leaking into buildings and damaging the interior, equipment, or furnishings.

There are two basic types of roofs, low-slope and steep-slope:

• Low-slope: About two-thirds of all roofs are low-slope. Most commercial, industrial, and apartment buildings have low-slope roofs. Low-slope roofs rise 4 inches or less per horizontal foot and are installed in layers.
  
  For low-slope roofs, roofers typically use several layers of roofing materials or felt membranes stuck together with hot bitumen (a tar-like substance). They glaze the top layer to make a smooth surface or embed gravel in the hot bitumen to make a rough surface.
  
  An increasing number of low-slope roofs are covered with a single-ply membrane of waterproof rubber or thermoplastic compounds.

• Steep-slope: Most of the remaining roofs are steep-slope. Most single-family houses have steep-slope roofs. Steep-slope roofs rise more than 4 inches per horizontal foot.
  
  For steep-slope roofs, roofers typically use asphalt shingles, which often cost less than other coverings. On steep-slope roofs, some roofers also install tile, solar shingles, fiberglass shingles, metal shingles, or shakes (rough wooden shingles).
  
  To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing over the entire roof. Then, starting from the bottom edge, they nail overlapping rows of shingles to the roof.

A small but increasing number of buildings now have “green” roofs that incorporate landscape roofing systems. A landscape roofing system typically begins with a single or multiple waterproof layers. After that layer is proven to be leak free, roofers put a root barrier over it, and, finally, layers of soil, in which vegetation is planted. Roofers must ensure that the roof is watertight and can endure the weight and water needs of the plants.

Tile and marble setters apply hard tile, marble, and wood tiles to walls, floors, and other surfaces.

Tile and marble setters typically do the following:

• Clean and level the surface to be tiled
• Measure and cut tile and marble
• Arrange tiles according to the design plans
• Prepare and apply mortar or other adhesives
• Install tile and marble in the planned area
• Apply grout with a rubber trowel
• Wipe off excess grout and apply necessary finishes, such as sealants

Tile installers, tilesetters, and marble setters install materials on a variety of surfaces, such as floors, walls, ceilings, countertops, patios, and roof decks. Because tile and marble must be set on smooth, even surfaces, installers often must level the surface to be tiled with a layer of mortar or plywood. If the area to be tiled is unstable, workers must nail a support of metal mesh or tile backer board to create a stable surface.

To cut tiles, workers use power wet saws, tile scribes, or hand-held tile cutters to create even edges. They use trowels of different sizes to spread mortar or a sticky paste, called mastic, evenly on the surface to be tiled. To minimize imperfections and keep rows straight and even, they put spacers between tiles. The spacers keep tiles the same distance from each other until the mortar is dry. After the mortar dries and the tiles are set, they apply grout between tiles using a rubber trowel (called a float).

Marble setters may cut marble to a specified size with a power wet saw. After putting the marble in place, marble setters polish the marble to a high luster, using power or hand sanders.

Occupational health and safety technicians collect data on the safety and health conditions of the workplace. Technicians work with occupational health and safety specialists in conducting tests and measuring hazards to help prevent harm to workers, property, the environment, and the general public. For more information, see the profile on occupational health and safety specialists.

Duties  

Occupational health and safety technicians typically do the following:

• Inspect, test, and evaluate workplace environments, equipment, and practices to ensure they follow safety standards and government regulations
• Collect samples of potentially toxic materials for analysis by occupational health and safety specialists
• Work with occupational health and safety specialists to control and fix hazardous and potentially hazardous conditions or equipment
• Carry out and evaluate programs on workplace safety and health
• Demonstrate the correct use of safety equipment
• Investigate accidents to identify why they happened and how they might be prevented in the future

Technicians conduct tests and collect samples and measurements as part of workplace inspections. For example, they may collect and handle samples of dust, mold, gases, vapors, or other potentially hazardous materials. They conduct both routine inspections and special inspections that a specialist orders. For more information about specialists, see the profile on occupational health and safety specialists.

Technicians may examine and test machinery and equipment such as scaffolding and lifting devices to be sure that they meet appropriate safety regulations. They may check that workers are using protective gear, such as masks and hardhats, as regulations say they must.

Technicians also check that hazardous materials are stored correctly. They test and identify work areas for potential health and safety hazards.

In addition to making workers safer, technicians work with specialists to increase worker productivity by reducing the number of worker absences and equipment downtime. They save companies money by lowering insurance premiums and worker compensation payments and by preventing government fines.

Technicians' duties vary based on where they are employed. For example, a technician may test the levels of biohazard at a waste processing plant or may inspect the lighting and ventilation in an office setting. Both of these inspections are focused on maintaining the health of the workers and the environment.

The responsibilities of occupational health and safety technicians vary by industry, workplace, and types of hazards affecting employees. The following are examples of types of occupational health and safety technicians:

Environmental protection technicians evaluate and coordinate the storage and handling of hazardous waste, the cleanup of contaminated soil or water, evaluation of air pollution, or other activities that affect the environment.

Health physics technicians work in places that use radiation and radioactive material. Their goal is to protect people and the environment from hazardous radiation exposure.

Industrial hygiene technicians examine the workplace for health hazards, such as exposure to lead, asbestos, pesticides, or contagious diseases.

Mine examiners inspect mines for proper air flow and health hazards such as the buildup of methane or other harmful gases.

Roofers repair and install the roofs of buildings using a variety of materials, including shingles, asphalt, and metal.

Roofers typically do the following:

• Inspect problem roofs to determine the best way to repair them
• Measure roof to calculate the quantities of materials needed
• Replace damaged or rotting joists or plywood
• Install vapor barriers or layers of insulation
• Install shingles, asphalt, metal, or other materials to make the roof watertight
• Align roofing materials with edges of the roof
• Cut roofing materials to fit angles formed by walls, vents, or intersecting roof surfaces
• Cover exposed nail or screw heads with roofing cement or caulk to prevent leakage

Properly installed roofs keep water from leaking into buildings and damaging the interior, equipment, or furnishings.

There are two basic types of roofs, low-slope and steep-slope:

• Low-slope: About two-thirds of all roofs are low-slope. Most commercial, industrial, and apartment buildings have low-slope roofs. Low-slope roofs rise 4 inches or less per horizontal foot and are installed in layers.
  
  For low-slope roofs, roofers typically use several layers of roofing materials or felt membranes stuck together with hot bitumen (a tar-like substance). They glaze the top layer to make a smooth surface or embed gravel in the hot bitumen to make a rough surface.
  
  An increasing number of low-slope roofs are covered with a single-ply membrane of waterproof rubber or thermoplastic compounds.

• Steep-slope: Most of the remaining roofs are steep-slope. Most single-family houses have steep-slope roofs. Steep-slope roofs rise more than 4 inches per horizontal foot.
  
  For steep-slope roofs, roofers typically use asphalt shingles, which often cost less than other coverings. On steep-slope roofs, some roofers also install tile, solar shingles, fiberglass shingles, metal shingles, or shakes (rough wooden shingles).
  
  To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing over the entire roof. Then, starting from the bottom edge, they nail overlapping rows of shingles to the roof.

A small but increasing number of buildings now have “green” roofs that incorporate landscape roofing systems. A landscape roofing system typically begins with a single or multiple waterproof layers. After that layer is proven to be leak free, roofers put a root barrier over it, and, finally, layers of soil, in which vegetation is planted. Roofers must ensure that the roof is watertight and can endure the weight and water needs of the plants.

Construction and building inspectors ensure that new construction, changes, or repairs comply with local and national building codes and ordinances, zoning regulations, and contract specifications.

Construction and building inspectors typically do the following:

• Review and approve plans that meet building codes, local ordinances, and zoning regulations
• Inspect and monitor construction sites to ensure overall compliance
• Use survey instruments, metering devices, and test equipment to perform inspections
• Monitor installation of plumbing, electrical, and other systems to ensure that the building meets codes
• Verify level, alignment, and elevation of structures and fixtures to ensure building compliance
• Issue violation notices and stop-work orders until building is compliant
• Keep daily logs, including photographs taken during inspection

Construction and building inspectors examine buildings, highways and streets, sewer and water systems, dams, bridges, and other structures. They also inspect electrical; heating, ventilation, air-conditioning, and refrigeration (HVACR); and plumbing systems. Although no two inspections are alike, inspectors do an initial check during the first phase of construction and follow-up inspections throughout the construction project. When the project is finished, they do a final, comprehensive inspection.

The following are types of construction and building inspectors:

Building inspectors check the structural quality and general safety of buildings. Some specialize in structural steel or reinforced-concrete structures, for example.

Electrical inspectors examine the installed electrical systems to ensure they function properly and comply with electrical codes and standards. The inspectors visit worksites to inspect new and existing sound and security systems, wiring, lighting, motors, and generating equipment. They also inspect the installed electrical wiring for HVACR systems and appliances.

Elevator inspectors examine lifting and conveying devices, such as elevators, escalators, moving sidewalks, lifts and hoists, inclined railways, ski lifts, and amusement rides.

Home inspectors typically inspect newly built or previously owned homes, condominiums, townhomes, and other dwellings. Prospective home buyers often hire home inspectors to check and report on a home's structure and overall condition. Sometimes, homeowners hire a home inspector to evaluate their home's condition before placing it on the market.

In addition to examining structural quality, home inspectors examine all home systems and features, including roofing, exterior walls, attached garage or carport, foundation, interior, plumbing, electrical, and HVACR systems. They look for and report violations of building codes, but they do not have the power to enforce compliance with the codes.

Mechanical inspectors examine the installation of HVACR systems and equipment to ensure that they are installed and function properly. They also may inspect commercial kitchen equipment, gas-fired appliances, and boilers.

Plan examiners determine whether the plans for a building or other structure comply with building codes. They also determine whether the structure is suited to the engineering and environmental demands of the building site.

Plumbing inspectors examine the installation of potable water, waste, and vent piping systems to ensure the safety and health of the drinking water system, piping for industrial uses, and the sanitary disposal of waste.

Public works inspectors ensure that federal, state, and local government water and sewer systems, highways, streets, bridges, and dam construction conform to detailed contract specifications. Workers inspect excavation and fill operations, the placement of forms for concrete, concrete mixing and pouring, asphalt paving, and grading operations. Public works inspectors may specialize in highways, structural steel, reinforced concrete, or ditches. Others specialize in dredging operations required for bridges and dams or for harbors.

Specification inspectors ensure that work is performed according to design specifications. Specification inspectors represent the owner's interests, not those of the general public. Insurance companies and financial institutions also may use their services.

A primary concern of building inspectors is fire prevention safety. For more information, see the profile on fire inspectors and investigators.

Forensic science technicians help investigate crimes by collecting and analyzing physical evidence. Most technicians specialize in either crime scene investigation or laboratory analysis.

At crime scenes, forensic science technicians, also known as crime scene investigators, typically do the following:

• Walk through the scene to determine what and how evidence should be collected
• Take photographs of the crime scene and evidence
• Make sketches of the crime scene
• Keep written notes of their observations and findings, such as the location and position of evidence as it is found
• Collect all relevant physical evidence, including weapons, fingerprints, and bodily fluids
• Catalog and preserve evidence before transferring it to a crime lab

Crime scene investigators may use tweezers, black lights, and specialized kits to identify and collect evidence. In addition to processing crime scenes, they may also attend autopsies.

In laboratories, forensic science technicians typically do the following:

• Identify and classify crime scene evidence through scientific analysis
• Explore possible links between suspects and criminal activity using the results of chemical and physical analyses
• Consult with experts in related or specialized fields, such as toxicology, about the evidence and their findings
• Reconstruct crime scenes based on scientific findings

Forensic science technicians reconstruct crime scenes by carefully studying information gathered by investigators and conducting scientific tests on physical evidence. For example, lab technicians may look at photographs of blood splatter patterns and conduct ballistics tests on bullets found at the crime scene to determine the direction from which a shot was fired.

Forensic science technicians who work in laboratories use chemicals and laboratory equipment such as microscopes when analyzing evidence. They also use computer databases to examine fingerprints, DNA, and other evidence collected at crime scenes in order to match them to people and things that have already been identified. Most forensic science technicians who perform laboratory analysis specialize in a specific type of evidence analysis, such as DNA or ballistics.

All forensic science technicians prepare written reports that detail their findings and investigative methods. They must be able to explain their reports to lawyers, detectives, and other law enforcement officials. In addition, forensic science technicians may be called to testify in court about their findings and methods.