Choose TOTAL HOME EXTERIORS to install and repair your business’s flat roof. A roof needs a drainage system. Homes in rainy climates require drainage, so flat roofs aren’t popular. Most “flat roofs” have slopes and aren’t flat. Most flat roofs are set at ten-degree angles or less. They look flat while and water a place to run. Drainage should be your number one concern when building a flat roof. The roof can be used as a terrace for celebrating functions, playing with children, etc.