Dormers on houses certainly are a common feature of many American homes. It is a relatively new design which includes also been used to provide support and shape to bridges. Two popular new trends for making both residential and commercial roofing more environmentally friendly are green roofs and solar roofs. A roof is considered to be pitched, if it has http://www.docdroid.net/wyf4/14286029025526c01650755.pdf.html a gradient greater than 15 degrees or perhaps a slope greater than 215 in 1 The main purpose of a pitched roof is to redirect the rainwater. Two popular new trends for making both residential and commercial roofing more green are green roofs and solar roofs.