Roofers - Main Roofers Roofers apply shingles and other materials to the roofs of buildings. Roofers usually cover flat roofs with several layers of materials. First they put down a layer of insulation. Then they spread a tar-like substance over the insulation.
Next roofers lay roofing felt and spread hot tar over it.
They repeat these steps, sealing the seams each time, to make layers. Roofers either glaze the top layer or embed it with gravel. Some flat roofs are covered with only a single layer of waterproof rubber or thermoplastic compounds. In these cases, roofers roll the sheets over the roof's insulation and seal the seams. They apply adhesives or mechanical fasteners to keep the sheets in place.