A commercial roof is more likely to have a flatter and plainer design when compared with a residential roof. These roofs also tend to be made of metal, which is much more expensive but has a longer life expectancy than standard shingles. The roofs are designed to be flat and metal for a few reasons, including the size and shape of the commercial building. Due to the lesser slope of commercial roofing, the roof is more likely to gather snow and debris brought about by the weather. The extra weight of these elements could cause structural damage, if not for the more robust construction of the metal roofing. This, added with the larger area and weight associated with a giant, flat, metal roof, means that the commercial roofing needs to be much more rigid to withstand the weight of itself and the longevity of its existence.
One concern about residential roofing that commercial roofing does not face is the aesthetic. A commercial roof cares about structural integrity and longevity, but due to the smaller size of a residential building, structural integrity and longevity are easy to come by. With less surface area comes less a need to worry about the roof holding up its own weight, so roofers can have a little bit of fun with their buildings. This gives the builders and roofers a chance to have more artistic freedom in the building of their roofs and can create all kinds of designs from butterfly to skillion designs. Not to mention most residential roofs are made from standard shingles, which are much less expensive than a similar metal roof.
The main similarities between residential and commercial roofing are the materials used in construction. While most buildings are made with the roofing materials as described above, this is not always true. Some residential homes are built with metal roofs, and the metal roofing is identical to the roofing on a commercial building, and vice versa. And most roofing companies do not specialize in one or the other; they typically have highly skilled teams that are able to construct both residential and commercial roofing.