Green Roof Gravel Ballast

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.

Green roof gravel ballast.

Slab ballast application or 0 0010 for a green roof or gravel ballast application has been assumed. The stones used in ballasted roofing are generally 1 5 2 5 inches in diameter and applied in a thicker layer. The single ply membrane and other roof components including thermal insulation are loose laid. The design of green roofs as well as traditional roofs.

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. Magazine and roofing southwest although single ply roofs inherently have sun protective qualities ballast provides an extra layer of protection from uv rays. It is recommended that the team involved in choosing a green roof provider should undertake the appropriate research. For built up roofing the gravel was generally 25 5 inches in diameter.

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. Simply put a ballasted roof is easy to install and basically guaranteed maintenance work for a roofer. The gravel in a ballasted roof helps absorb heat preventing the sun from heating the roof materials below and making the roof more energy efficient. Despite the positive qualities associated with a ballasted roof system there are some challenges.

This research should include reviewing the complexity and size of green roofs. Somebody walking on the roof will undoubtedly step on the ballast and put a hole in the membrane. They assume a nominal selection of post codes selected to represent the infl uence of geographical variations in rainfall on thermal performance. They are valid for the constructions shown in the details immediately above each table.

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. Roof gravel provides a protective layer to flat roofs reducing the weather damaging effects from uv rays and heavy snow hail and wind. The buildup is ballasted with a gravel layer of at least 50 mm and 80 kg m 2. Gravel ballasted roofs with sikaplan or sarnafil single ply membranes are conventionally installed.

Too much gravel can result in a structural issue due to weight. Ballasted roof systems are simultaneously a roofer s best friend and arch nemesis. 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. It also provides protection from foot traffic.