Roofers Information from the Occupational Outlook Handbook.
- Most Roofers learn their skills informally on the job; some roofers train through 3-year apprenticeships.
- Most job openings will arise from the need to replace those who leave the occupation because the work is hot, strenuous, and dirty, causing many people to switch to jobs in other construction trades.
- Demand for roofers is less susceptible to downturns in the economy than demand for other construction trades because most roofing work consists of repair and reroofing.
Nature of the Work
A leaky roof can damage ceilings, walls, and furnishings. Roofers repair and install roofs made of tar or asphalt and gravel; rubber or thermoplastic; metal; or shingles to protect buildings and their contents from water damage. Repair and reroofing—replacing old roofs on existing buildings—makes up the majority of work for roofers.
There are two types of roofs—low-slope and steep-slope. Low-slope roofs rise 4 inches per horizontal foot or less and are installed in layers. Steep-slope roofs rise more than 4 inches per horizontal foot and are usually covered in shingles. Most commercial, industrial, and apartment buildings have low-slope roofs. Most houses have steep-slope roofs. Some roofers work on both types; others specialize.
Most low-slope roofs are covered with several layers of materials. Roofers first put a layer of insulation on the roof deck. Over the insulation, they often spread a coat of molten bitumen, a tarlike substance. Next, they install partially overlapping layers of roofing felt—a fabric saturated in bitumen—over the surface. Roofers use a mop to spread hot bitumen over the felt before adding another layer of felt. This seals the seams and makes the surface watertight. Roofers repeat these steps to build up the desired number of layers, called “plies.” The top layer is glazed to make a smooth finish or has gravel embedded in the hot bitumen to create a rough surface.
An increasing number of low-slope roofs are covered with a single-ply membrane of waterproof rubber or thermoplastic compounds. Roofers roll these sheets over the roof’s insulation and seal the seams. Adhesive, mechanical fasteners, or stone ballast hold the sheets in place. Roofers must make sure the building is strong enough to hold the stone ballast.
A small but growing number of buildings now have “green” roofs that incorporate plants. A “green” roof begins with a single or multi-ply waterproof layer. After it is proven to be leak free, roofers put a root barrier over it, and then layers of soil, in which trees and grass are planted. Roofers are usually responsible for making sure the roof is watertight and can withstand the weight and water needs of the plants.
Most residential steep-slope roofs are covered with shingles. To apply shingles, roofers first lay, cut, and tack 3-foot strips of roofing felt over the entire roof. Starting from the bottom edge, the roofer then staples or nails overlapping rows of shingles to the roof. Roofers measure and cut the felt and shingles to fit intersecting roof surfaces and to fit around vent pipes and chimneys. Wherever two roof surfaces intersect, or shingles reach a vent pipe or chimney, roofers cement or nail flashing-strips of metal or shingle over the joints to make them watertight. Finally, roofers cover exposed nailheads with roofing cement or caulking to prevent water leakage. Roofers who use tile, metal shingles, or shakes (rough wooden shingles) follow a similar process.
Roofers also install equipment that requires cutting through roofs, such as ventilation ducts and attic fans. Some roofers are expert in waterproofing; some waterproof and dampproof masonry and concrete walls, floors, and foundations. To prepare surfaces for waterproofing, they hammer and chisel away rough spots or remove them with a rubbing brick, before applying a coat of liquid waterproofing compound. They also may paint or spray surfaces with a waterproofing material or attach waterproofing membrane to surfaces. Roofers usually spray a bitumen-based coating on interior or exterior surfaces when dampproofing.
Work environment. Roofing work is strenuous. It involves heavy lifting, as well as climbing, bending, and kneeling. Roofers work outdoors in all types of weather, particularly when making repairs. However, they rarely work when it rains or in very cold weather as ice can be dangerous. In northern States, roofing work is generally not performed during winter months. During the summer, roofers may work overtime to complete jobs quickly, especially before forecasted rainfall.
Workers risk slips or falls from scaffolds, ladders, or roofs or burns from hot bitumen, but safety precautions, can prevent most accidents. In addition, roofs can become extremely hot during the summer, causing heat-related illnesses. In 2005, the rate of injuries for roofing contractors in construction was almost twice that of workers overall.
Training, Other Qualifications, and Advancement
Most roofers learn their skills informally by working as helpers for experienced roofers and by taking classes, including safety training, offered by their employers; some complete 3-year apprenticeships.
Education and training. A high school education, or its equivalent, is helpful and so are courses in mechanical drawing and basic mathematics. Although most workers learn roofing as helpers for experienced workers, some roofers train through 3-year apprenticeship programs administered by local union-management committees representing roofing contractors and locals of the United Union of Roofers, Waterproofers, and Allied Workers. Apprenticeship programs usually include at least 2,000 hours of paid on-the-job training each year, plus a minimum of 144 hours of classroom instruction a year in tools and their use, arithmetic, safety, and other topics. On-the-job training for apprentices is similar to the training given to helpers, but an apprenticeship program is more structured and comprehensive. Apprentices, for example, learn to dampproof and waterproof walls.
Trainees start by carrying equipment and material and erecting scaffolds and hoists. Within 2 or 3 months, they are taught to measure, cut, and fit roofing materials and, later, to lay asphalt or fiberglass shingles. Because some roofing materials are used infrequently, it can take several years to get experience working on all types of roofing.
Other qualifications. Good physical condition and good balance are essential for roofers. They cannot be afraid of heights. Experience with metal-working is helpful for workers who install metal roofing. Usually, apprentices must be at least 18 years old.
Advancement. Roofers may advance to become supervisors or estimators for a roofing contractor or become contractors themselves.
Roofers held about 156,000 jobs in 2006. Almost all salaried roofers worked for roofing contractors. About 20 percent of roofers were self-employed. Many self-employed roofers specialized in residential work.