Green Roof Gravel Ballast

Simply put a ballasted roof is easy to install and basically guaranteed maintenance work for a roofer.

Green roof gravel ballast.

Ballasted green systems roof materials for ballasted green systems a ballasted gravel paved roof will generally require a stronger supporting structure than that for the exposed membrane one but will allow the roof to be used as a trafficked or leisure use area. Despite the positive qualities associated with a ballasted roof system there are some challenges. Too much gravel can result in a structural issue due to weight. Green roof temperatures can be 30 40 f lower than those of conventional roofs and can reduce city wide ambient temperatures by up to 5 f.

Ballasted roof systems are simultaneously a roofer s best friend and arch nemesis. It is recommended that the team involved in choosing a green roof provider should undertake the appropriate research. The buildup is ballasted with a gravel layer of at least 50 mm and 80 kg m 2. This is inch per 1 foot which is the norm minimum roof slope for drainage.

1 2 in addition green roofs can reduce building energy use by 0 7 compared to conventional roofs reducing peak electricity demand and leading to an annual savings of 0 23 per square foot of the roof. It is very important to note that the amount of gravel being applied to a roof must be precise it depends on the specific roofing spec being used and the building type. Roofstone can also be used on roofs that must be ada compliant with slope up to 1 48 which equals 2 08 or 1 19 degrees. Magazine and roofing southwest although single ply roofs inherently have sun protective qualities ballast provides an extra layer of protection from uv rays.

Somebody walking on the roof will undoubtedly step on the ballast and put a hole in the membrane. For built up roofing the gravel was generally 25 5 inches in diameter. Roofstone follows the roof contour and can be used to create walkways patios and landing areas on most non ada compliant roofs. The stones used in ballasted roofing are generally 1 5 2 5 inches in diameter and applied in a thicker layer.

This document is not a how to manual on green roof. The design of green roofs as well as traditional roofs. The single ply membrane and other roof components including thermal insulation are loose laid. The gravel used in built up roofing what the roofing contractors were used to was not the same as that used in a ballasted roof.

They are valid for the constructions shown in the details immediately above each table. Gravel ballasted roofs with sikaplan or sarnafil single ply membranes are conventionally installed. This research should include reviewing the complexity and size of green roofs. Holes mean roof leaks and roof leaks mean call the roofer.