Roof Ballast Material

Ballasted roof systems are simultaneously a roofer s best friend and arch nemesis.

Roof ballast material.

A ballasted roof means that the roof membrane is not anchored or adhered in any way to the decking material. 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. Additional benefits of ballast on a flat roof. Somebody walking on the roof will undoubtedly step on the ballast and put a hole in the membrane.

Ballast options and flexibility. Roofs with pavers as ballast can be used as outdoor patios. Ballasted flat roofs are a popular choice especially for commercial buildings. Adds a lot of weight to the roof system typically 10 15 pounds per square feet.

Note that roof systems typically include more than one type of material a built up roof for example will typically include the built up membrane itself with or without gravel as well as some kind of insulation and cover board which will vary in thickness from roof to roof. When the concept first came to the u s plenty of roofers scratched their heads and wondered how the roof stayed on without being anchored especially during high winds or storms. Simply put a ballasted roof is easy to install and basically guaranteed maintenance work for a roofer. Ballast stone traps a lot of dirt making patching difficult.

It is however ballasted generally with gravel. Magazine and roofing southwest although. Drawbacks of a ballasted roof system.