Flood Control

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.

Boilermakers assemble, install, and repair boilers, closed vats, and other large vessels or containers that hold liquids and gases.

Boilermakers typically do the following:

• Use blueprints to determine locations, positions, or dimensions of parts
• Install small premade boilers into buildings and manufacturing facilities
• Lay out prefabricated parts of larger boilers before assembling them
• Assemble boiler tanks, often using robotic or automatic welders
• Test and inspect boiler systems for leaks or defects
• Clean vats using scrapers, wire brushes, and cleaning solvents
• Replace or repair broken valves, pipes, or joints, using hand and power tools, gas torches, and welding equipment

Boilers, tanks, and vats are used in many buildings, factories, and ships. Boilers heat water or other fluids under extreme pressure to generate electric power and to provide heat. Large tanks and vats are used to store and process chemicals, oil, beer, and hundreds of other products.

Boilers are made out of steel, iron, copper, or stainless steel. Manufacturers are increasingly automating the production of boilers to improve the quality of these vessels. However, boilermakers still use many tools in making or repairing boilers. For example, they use hand and power tools or flame cutting torches to cut pieces for a boiler. To bend the pieces into shape and accurately line them up, boilermakers use plumb bobs, levels, wedges, and turnbuckles.

If the plate sections are very large, large cranes lift the parts into place. Once they have the parts lined up, they use metalworking machinery and other tools to remove irregular edges so the parts fit together properly. They join the parts by bolting, welding, or riveting them together.

In addition to installing and maintaining boilers and other vessels, boilermakers help erect and repair air pollution equipment, blast furnaces, water treatment plants, storage and process tanks, and smokestacks. Boilermakers also install refractory brick and other heat-resistant materials in fireboxes or pressure vessels. Some install and maintain the huge pipes used in dams to send water to and from hydroelectric power generation turbines.

Because boilers last a long time--sometimes 50 years or more--boilermakers must regularly maintain them and upgrade parts. They frequently inspect fittings, feed pumps, safety and check valves, water and pressure gauges, and boiler controls.

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.

Janitors and building cleaners keep many types of buildings clean, orderly, and in good condition.

Janitors and building cleaners typically do the following:

• Gather and empty trash and trash bins
• Clean building floors by sweeping, mopping, or vacuuming them
• Clean bathrooms and stock them with soap, toilet paper, and other supplies
• Keep buildings secure by locking doors
• Clean spills and other hazards using sponges and squeegees
• Wash windows, walls, and glass
• Order cleaning supplies
• Make minor repairs to the building, such as changing light bulbs
• Notify managers when the building needs major repairs

Janitors and building cleaning workers keep office buildings, schools, hospitals, retail stores, hotels, and other places clean, sanitary, and in good condition. Some do only cleaning, while others have a wide range of duties.

In addition to keeping the inside of buildings clean and orderly, some janitors and building cleaners work outdoors, mowing lawns, sweeping walkways, or shoveling snow. Some janitors also monitor the heating and cooling system, ensuring that it functions properly.

Janitors and building cleaners use many tools and equipment. Simple cleaning tools may include mops, brooms, rakes, and shovels. Other tools may include snowblowers and floor buffers.

Some janitors may be responsible for repairing small problems with electricity or plumbing, such as leaky faucets.