Green Roof Gravel Ballast

The single ply membrane and other roof components including thermal insulation are loose laid.

Green roof gravel ballast.

Despite the positive qualities associated with a ballasted roof system there are some challenges. Holes mean roof leaks and roof leaks mean call the roofer. 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.

The design of green roofs as well as traditional roofs. Ballasted roof systems are simultaneously a roofer s best friend and arch nemesis. They are valid for the constructions shown in the details immediately above each table. Magazine and roofing southwest although single ply roofs inherently have sun protective qualities ballast provides an extra layer of protection from uv rays.

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. 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. This document is not a how to manual on green roof. 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. Too much gravel can result in a structural issue due to weight. This research should include reviewing the complexity and size of green roofs. They assume a nominal selection of post codes selected to represent the infl uence of geographical variations in rainfall on thermal performance.

The buildup is ballasted with a gravel layer of at least 50 mm and 80 kg m 2. Roofstone follows the roof contour and can be used to create walkways patios and landing areas on most non ada compliant roofs. Gravel ballasted roofs with sikaplan or sarnafil single ply membranes are conventionally installed. 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.

Simply put a ballasted roof is easy to install and basically guaranteed maintenance work for a roofer. For built up roofing the gravel was generally 25 5 inches in diameter. 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. It is recommended that the team involved in choosing a green roof provider should undertake the appropriate research.