The following roof coverings are commonly used on steep-slope roofs. These coverings are water shedding, rather than waterproofing. Special underlayment provisions are required when slopes are relatively low. The NRCA Roofing Manual provides underlayment guidance.
Hydrokinetic Metal Roofs come in two different forms. The first kind is known as an R-Panel (screw down) roof. The second type is known as a Standing-Seam system. Both have their advantages and disadvantages. The primary difference is R-Panel is less expensive to install and Standing-Seam is less likely to require major repairs. R-Panel roofs will require the screws to be replaced every 10 – 15 years with larger screws, because thermal cycling will cause the pilot holes to slowly expand as they rub against the screws. Standing-Seam roofs do not require this type of maintenance, as the fastening system is hidden.
Slate is one of the most time tested roof solutions in the world, and is considered a family heirloom to many who have had the same roof on their stylish house/building. Slates aesthetic appeal is unrivaled, as is it’s longevity. Many slate roofs have been known to last more than a century. This class of roof comes with a high price point and the need for excellent structural support, however. Due to these reasons, many do not find slate to be a viable option for their property.