Most (not all) roofers provide commercial roof repair as well as work on residential roofs (along with work on gutters and windows and siding and more). How different are the materials and design between these commercial buildings and, say, the roof above your head at home?
For starters, the pitch is often very different. The pitch refers to the angle of slope of the roof. On the roof of a business or other commercial space, the slope of the roof is usually quite small. With just a few degrees of angle from flat, or parallel with the ground, these commercial spaces often appear to have roofs that flat straight across.
Homes, apartment buildings, condos, and other personal living spaces can have much steeper pitch – some as much as 45 degrees, though those are increasingly less common.
One reason for this difference is the size of the roof. Homes are generally much, much smaller than commercial spaces, so their roof dimensions are smaller as well, in terms of ground covered. If a huge commercial space had a steeply-angled roof, then the roof would have to be ridiculously high at its tallest point. It simply does not make sense from a construction perspective.
The materials used in residential and commercial settings are different as well. Most houses and condos have asphalt shingles, in part because they are inexpensive and relatively easy to install. Homes have shingles that are comprised of wood shakes, slate, tile, ceramics, or metal panels too.
Since the roofs of businesses are more flat, other materials tend to work better. These commercial roofs are often covered with gravel, tar, modified bitumen, or single-ply materials like EPDM (ethylene propylene diene terpolymer). TPO, (thermoplastic polyolefin) or PVC (polyvinyl chloride). Installers often spray polyurethane foam on these commercial roofs as well.