Roof Ballast Depth

The depth of the ballast or media contained in the trays can be varied depending on the desire to reduce the presence of open water surfaces.

Roof ballast depth.

Ballasted roof systems are simultaneously a roofer s best friend and arch nemesis. The heavier stones provide substantial protection against wind gusts. 2 the membranes tend to pull at their perimeter ties raising and stretching the. Stone ballast typically requires crushed graded stone placed over a stone filter sheet rolled out over the insulation.

Additional benefits of ballast on a flat roof. Modular trays can have a variety of different outlet designs according to the goals of the installation e g reduce peak flows achieve specific lag time for target events etc. Track ballast should never be laid down less than 150 mm 6 inches thick and high speed railway lines may require ballast up to 0 5 metres 20 inches thick. Finally the ballast stone or and pavers are laid down throughout the roof system.

Divide the amount of ballast to be added or removed by 64 1. Somebody walking on the roof will undoubtedly step on the ballast and put a hole in the membrane. Seawater weighs 64 1 pounds per cubic foot. Needed at perimeters and at large penetrations.

Ballast is required with 20 lbs s f. If you remove 64 1 pounds of ballast then the vessel will displace 1 cubic foot of water less than it did before the 64 1 pounds of ballast was removed. Generally loose laid ballasted roofing systems are not recommended or at least discouraged for three reasons. Contact hydrotech for specific installation guidelines.

Ballasted flat roofs are a popular choice especially for commercial buildings. Simply put a ballasted roof is easy to install and basically guaranteed maintenance work for a roofer. Most roofers typically installed 10 15 pounds of ballast per square foot. Or you may call us at 440 946 2233.

An insufficient depth of ballast causes overloading of the underlying soil and in unfavourable conditions overloading the soil causes the track to sink usually unevenly. 1 a leak is very difficult to locate because the water runs freely in numerous directions and for longer distances under the loose laid membrane. Holes mean roof leaks and roof leaks mean call the roofer. In the field of the roof a minimum of 10 lbs s f.

Ballast stones are usually one to two inches thick and applied more generously than on a built up roof. Roofing southwest a ballast system helps cut roof system application costs as it takes less time to install since sealing the layers together isn t necessary. Though not as common as they used to be ballasted roof systems still prove to be a viable solution for today s commercial roof needs. Benefits of a ballasted roof system.

The weight of the ballast equals the weight of the water it causes the vessel to displace. For built up roofing the gravel was generally 25 5 inches in diameter. Installs very quickly since no fasteners or adhesives are used. Doesn t produce any foul smell during construction.