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.


Environmental Engineering Technicians

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, and Tapers

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.


Heating, Air Conditioning, and Refrigeration Mechanics and Installers

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.


Fire Inspectors and Investigators

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.


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