Roof Ballast Depth

Seawater weighs 64 1 pounds per cubic foot.

Roof ballast depth.

For built up roofing the gravel was generally 25 5 inches in diameter. Needed at perimeters and at large penetrations. 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. The weight of the ballast equals the weight of the water it causes the vessel to displace.

To learn more about selecting a commercial roofer in cleveland ohio simply fill out the form on this page and a member of our team will be in touch. 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. The stones used in ballasted roofing are generally 1 5 2 5 inches in diameter and applied in a thicker layer. Most roofers typically installed 10 15 pounds of ballast per square foot.

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. Ballasted roof systems are simultaneously a roofer s best friend and arch nemesis. 2 the membranes tend to pull at their perimeter ties raising and stretching the. Installs very quickly since no fasteners or adhesives are used.

In the field of the roof a minimum of 10 lbs s f. The heavier stones provide substantial protection against wind gusts. Divide the amount of ballast to be added or removed by 64 1. 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.

Somebody walking on the roof will undoubtedly step on the ballast and put a hole in the membrane. Simply put a ballasted roof is easy to install and basically guaranteed maintenance work for a roofer. Ballasted flat roofs are a popular choice especially for commercial buildings. Contact hydrotech for specific installation guidelines.

Additional benefits of ballast on a flat roof. Stone ballast typically requires crushed graded stone placed over a stone filter sheet rolled out over the insulation. Or you may call us at 440 946 2233. Finally the ballast stone or and pavers are laid down throughout the roof system.

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. Generally loose laid ballasted roofing systems are not recommended or at least discouraged for three reasons. Benefits of a ballasted roof system. Doesn t produce any foul smell during construction.

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. 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. Ballast is required with 20 lbs s f. Ballast stones are usually one to two inches thick and applied more generously than on a built up roof.