Kent Elliott Roofing

Construction equipment operators drive, maneuver, or control the heavy machinery used to construct roads, bridges, buildings, and other structures.

Construction equipment operators typically do the following:

• Check to make sure that equipment functions properly
• Clean, maintain, and make basic repairs to equipment
• Report malfunctions to supervisors
• Move levers, push pedals, or turn valves to activate power equipment
• Drive and maneuver equipment
• Coordinate machine actions with crew members in response to hand or audio signals
• Ensure that safety standards are met

Construction equipment operators use machinery to move construction materials, earth, and other heavy materials at construction sites and mines. They operate equipment that clears and grades land to prepare it for construction of roads, bridges, and buildings, as well as airport runways, power generation facilities, dams, levees, and other structures.

The following are types of construction equipment operators:

Operating engineers and other construction equipment operators work with one or several types of power construction equipment. They may operate excavation and loading machines equipped with scoops, shovels, or buckets that dig sand, gravel, earth, or similar materials. In addition to operating the familiar bulldozer, they operate trench excavators, road graders, and similar equipment. Sometimes, they may drive and control industrial trucks or tractors equipped with forklifts or booms for lifting materials. They also may operate and maintain air compressors, pumps, and other power equipment at construction sites.

Paving and surfacing equipment operators control the machines that spread and level asphalt or spread and smooth concrete for roadways or other structures. Paving and surfacing equipment operators may specialize further:

• Asphalt spreader operators turn valves to regulate the temperature of asphalt and the flow of asphalt onto the roadbed. They must ensure that the machine distributes the paving material evenly, and they also must ensure that there is a constant flow of asphalt into the hopper.
• Concrete paving machine operators control levers and turn handwheels to move attachments that spread, vibrate, and level wet concrete. They must watch the surface of the concrete carefully to identify low spots into which workers must add concrete.
• Tamping equipment operators use machines that compact earth and other fill materials for roadbeds or other construction sites. They also may operate machines with interchangeable hammers to cut or break up old pavement and drive guardrail posts into the ground.

Piledriver operators use large machines mounted on skids, barges, or cranes to hammer piles into the ground. Piles are long, heavy beams of wood or steel driven into the ground to support retaining walls, bridges, piers, or building foundations. Some piledriver operators work on offshore oil rigs.

Some workers operate cranes to move construction materials. For more information on these workers, see the profile on material moving machine operators.

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.

Heating, air conditioning, and refrigeration mechanics and installers--often referred to as HVACR technicians--work on heating, ventilation, cooling, and refrigeration systems that control the air quality in many types of buildings.

Heating, air conditioning, and refrigeration mechanics and installers typically do the following:

• Travel to worksites
• Follow blueprints or other design specifications to install or repair HVACR systems
• Connect systems to fuel and water supply lines, air ducts, and other components
• Install electrical wiring and controls and test for proper operation
• Inspect and maintain customers' HVACR systems
• Test individual components to determine necessary repairs
• Repair or replace worn or defective parts

Heating and air conditioning systems control the temperature, humidity, and overall air quality in homes, businesses, and other buildings. By providing a climate controlled environment, refrigeration systems make it possible to store and transport food, medicine, and other perishable items.

Although trained to do all three, HVACR technicians sometimes work strictly with heating, air conditioning, or refrigeration systems. They also may specialize in certain types of HVACR equipment, such as water-based heating systems, solar panels, or commercial refrigeration.

Depending on the task, HVACR technicians use many different tools. For example, they often use screwdrivers, wrenches, pipe cutters and other basic handtools when installing systems. To test or install complex system components, technicians may use more sophisticated tools, such as carbon monoxide testers, voltmeters, combustion analyzers, and acetylene torches.

When working on air conditioning and refrigeration systems, technicians must follow government regulations regarding the conservation, recovery, and recycling of refrigerants. This often entails proper handling and disposal of fluids.  

Some HVACR technicians sell service contracts to their clients, providing regular maintenance of heating and cooling systems.

Other craft workers sometimes help install or repair cooling and heating systems. For example, on a large air conditioning installation job, especially one in which workers are covered by union contracts, ductwork might be done by sheet metal workers and duct installers, or electrical work by electricians. In addition, home appliance repairers usually service window air conditioners and household refrigerators. For more information on these occupations, see the profiles on sheet metal workers, electricians, or home appliance repairers.

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.

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.

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.

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.

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.

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.

Environmental engineering technicians engineering technicians carry out the plans that environmental engineers develop.

Environmental engineering technicians typically do the following:

• Set up, test, operate, and modify equipment for preventing or cleaning up environmental pollution
• Maintain project records and computer program files
• Conduct pollution surveys, collecting and analyzing samples such as air and ground water
• Perform indoor and outdoor environmental quality work
• Work to mitigate sources of environmental pollution
• Review technical documents to ensure completeness and conformance to requirements
• Review work plans to schedule activities
• Arrange for the disposal of lead, asbestos, and other hazardous materials

In laboratories, environmental engineering technicians record observations, test results, and document photographs. To keep the laboratory supplied, they also may get product information, identify vendors and suppliers, and order materials and equipment.

Environmental engineering technicians also help environmental engineers develop devices for cleaning up environmental pollution. They also inspect facilities for compliance with the regulations that govern substances such as asbestos, lead, and wastewater.

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.

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.

Hydrologists study water and the water cycle. They study the movement, distribution, and other properties of water, and they analyze how these influence the surrounding environment. They use their expertise to solve problems concerning water quality and availability, for example.

Hydrologists typically do the following:

• Measure the properties of bodies of water, such as volume and stream flow
• Collect water and soil samples to test for certain properties, such as levels of pollution
• Apply research findings to help minimize the environmental impacts of pollution, erosion, and other problems
• Research ways to improve water conservation and preservation
• Use computer models to forecast future water supplies, the spread of pollution, and other events
• Evaluate the feasibility of water-related projects, such as hydroelectric power plants, irrigation systems, and waste treatment facilities
• Prepare written reports and presentations of their findings

Hydrologists use remote sensing equipment to collect data. They or technicians whom they supervise usually install and maintain this equipment.

They also use sophisticated computer programs to analyze and model data. They use sophisticated laboratory equipment to analyze chemical samples collected in the field.

Hydrologists work closely with engineers, scientists, and public officials to study and manage the water supply. For example, they work with policy makers to develop water conservation plans and with biologists to monitor marine wildlife.

Most hydrologists specialize in a specific water source or a certain aspect of the water cycle, such as the evaporation of water from lakes and streams. Some of the most common specialties are:

Groundwater hydrologists study the water below the Earth's surface. They decide the best locations for wells and the amount of water that should be pumped. They are often consulted about the best places to build waste disposal sites to ensure that the waste does not contaminate the groundwater.

Hydrometeorologists study the relationship between surface waters and water in the atmosphere. For example, to predict and prepare for droughts, they study how much rain or snow a particular area gets and how that evaporates.

Surface water hydrologists study water from above ground sources such as streams, lakes, and snow packs. They may predict future water levels and usage to help reservoir managers decide when to release or store water. They also produce flood forecasts and help develop flood management plans.

Some people with a hydrology background become professors or teachers. For more information, see the profile on postsecondary teachers.

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.

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

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 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.

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.

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.

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.

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.

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.

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.