Live Load Of Flat Roof

For roofs that are flat and with ground snow loads lower than 20 pounds per square foot the roof snow load is equal to 70 of the product of the exposure thermal and importance factors and the ground snow load.

Live load of flat roof.

Where uniform roof live loads are reduced to less than 20 psf 0 96 kn m 2 in accordance with section 1607 13 2 1 and are applied to the design of structural members arranged so as to create continuity the reduced roof live load shall be applied to adjacent spans or to alternate spans whichever produces the most unfavorable load effect. Roof loads are a downward vertical force on the home. Roof load live load design is affected by the shape of the roof whether it is flat curved or pitched. If your roof is 1 000 square feet the total snow load is 15 000 pounds of snow.

Where snow isn t a problem the live load can come from people working on the roof and any equipment they take on to the. Roofs of buildings used for promenade or incidental assembly purposes shall be designed for a minimum load of 400 kg m2 4 kn m2 or heavier it required. Used but they typically defined the load cases or combination stress or strength limits and deflection limits. The live load on a roof is the weight of any temporary objects on the roof.

To figure out the load on your roof take the depth of snow in feet and multiply it by the weight of a cubic foot of snow. The north zone middle zone and the south zone are identified on the roof load zone map above. Load types loads used in design load equations are given letters by type. This downward imposed load on the home is also known as the snow load.

Further in most areas of the united states design winds are produced by either hurricanes or thunderstorms. Axial forces from snow loads and roof live loads should usually not be considered simultaneously with an extreme wind load because they are mutually exclusive on residential sloped roofs. If the snow weighs 10 pounds per cubic foot and there are 1 5 feet on the roof each square foot of the roof is getting 15 pounds of pressure. But when we discuss roofs these days live loads are generally associated with the weight that the roof structure might be asked to endure while the roof is under construction or renovation reroofing.