Weight Of Ballasted Roof

Gravel in form of round smooth river washed aggregate without broken pieces nominal 16 to 32 mm.

Weight of ballasted roof.

In the case of ballasted roofs ballast will consist of rounded gravel 20 40 mm diameter at a minimum rate of 80 kg per square metre and 50 mm thickness or pre cast hydraulically pressed concrete pavers of 50 mm minimum thickness and approximately 120kg m2. Drawbacks of a ballasted roof system adds a lot of weight to the roof system typically 10 15 pounds per square feet. 52 5 97 65 kg. The single ply membrane and other roof components including thermal insulation are loose laid.

While a higher degree tilt can yield more energy the tradeoff is that the higher tilt acts like a sail and creates uplift that requires more ballast blocks and weight on the roof. After combining the weight of components i e. The buildup is ballasted with a gravel layer of at least 50 mm and 80 kg m 2. The gravel ballast secures the roof waterproofing against wind uplift forces.

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. Epdm roof membrane 60 mil ballasted membrane and stone ballast only 10 75 20 lbs. Once completed the epdm membrane is held in place using one of the following materials as ballast with a minimum weight of 50 kg m. Roof perimeters and penetrations are flashed in accordance with firestone specifications pdf.

None asphalt roll roofing 1 1 lb m ft 2 5 4 kg m 2 asphalt shingle or asphalt fiberglass composite shingle 2 7 lb m ft 2 13 2 kg m 2. 1075 2000 lbs. Multi story buildings and perimeters will often require more than 10 psf ballast for. Don t forget to add all roof assembly materials when calculating total roof weight.

This includes the roof deck and the supporting structure typically roof trusses and or rafters as well as the roof system itself. Previous all faqs next. Insulation membrane fasteners and adhesive typical installation weight is less than 2 pounds per square foot 10 kg per square meter when 060 thick membrane typically weighing 1 3 pound per square foot or 1 6 kg per square meter is utilized. Ballasted roof dead load jike structural 19 jun 14 22 09.

A loose ballasted roof where you have 1 to 2 inches of gravel is more on the order of 12 psf. Check out eng tips forum s policies here. The weight of roofing constructions above the truss rafter may be estimated with the calculator below. The weight on a ballasted roof can be from 10 to 25 pounds per square foot meaning the substructure must be designed specifically to carry more weight than other roofing systems.

Extremely difficult to find a leak in this system since the membrane is well hidden. Select a ballast tilt for your modules. Ballast stone fractures and gets.