The work of roofers is to install and repair roofs made of asphalt, tar, gravel, metal, rubber, shingles, or thermoplastic to protect buildings and their parts from water damage. There are two kinds of roofs steep-slope and low-slope.
Low-slope roofs go up to four inches per horizontal foot, which is installed in layers. Steep-slope roofs rise over four inches per horizontal foot and are normally covered in shingles. Many industrial, commercial, and apartment buildings have low-slope roofs whereas many houses have steep-slope roofs.
Roofers have to install both the kinds of roofs. They first put a layer of insulation on the roof deck. On the insulation, they spread a coat of tar-like substance and molten bitumen. Then they install partly overlapping layers of roofing felt, a fabric saturated in bitumen over the surface. Roofers have to use a swab to spread hot bitumen over the felt before applying another layer of felt. This seals the seams and enhances surface watertight. Roofers replicate these steps to establish the desired number of layers called, �plies'.
A low-slope roofs are covered with a thermoplastic compounds or a single-ply covering of waterproof rubber. Roofers have to roll these sheets over the roof's insulation and seal the seams. Glue, stone ballast, or mechanical fasteners hold the sheets in place. Roofers should ensure that the building is strong enough to hold the stone ballast.
Nowadays, many buildings have �green' roofs that consist of plants. A �green' roof incorporates a single or multi-ply waterproof layer. Once it is confirmed to be leak free, roofers have to put a root barrier over it, layers of soil in which grass and trees are planted. Usually, roofers are accountable for ensuring the roof is watertight and can endure water and weight needs of the plants.
Some residential steep-roofs are covered with shingles. A roofer has to cut, lay, and tack three-foot strips of roofing felt over the complete roof in order to apply shingles. Consequently, roofer nails or staples overlapping rows of shingles to the roof. Roofers have to cut and measure the felt and shingles to fit interconnecting roof surfaces and to fit around chimneys and vent pipes. Roofer nails or cements shingle or flashing-strips of metal over the joints to formulate them watertight. Roofers cover exposed nail heads with caulking or roofing cement to prevent water leakage.
Roofers install equipments, which require cutting through roofs such as attic fans and ventilation ducts. Some roofers specialize in waterproofing, some damp-proof masonry and waterproof, some concrete walls, foundations, and floors. To make surfaces for waterproofing, roofers hammer and form rough spots or remove them with a rubbing brick. Consequently, they apply a coat of liquid waterproofing compound. Roofers may spray or paint surfaces, attach waterproofing membrane or water proofing materials.
Sometimes, roofing work is exhausting. It consists of heavy lifting, bending, kneeling, and climbing. Roofers have to work outdoors in all kinds of weather, especially, when making repairs. Nevertheless, they have to work even in rains or in extreme cold weather, which may be dangerous. Generally, roofing work is not executed in northern states during winter season. Roofers tend to complete work quickly, especially, before predicted rainfall.
Safety precautions may prevent accidents like fall from scaffolds, roofs, ladders, and burn from hot bitumen. Additionally, roofs may become extremely hot during summer that may affect health of roofers. Therefore, roofers have to take care before working in such type of conditions. A roofer has to carry out following responsibilities.
Some employers offer on-the-job training to their employees. These roofers enhance their skills by assisting experienced roofers on the workplace. Some roofers complete a three-year apprenticeship. Candidates who completed a high school education or equivalent with courses in basic mathematics and mechanical drawing are preferred.