Roof Live Load Example

The commentary in asce 7 05 c4 about roof live load reductions explains the anticipated difference in use of roof areas vs.

Roof live load example.

Typically roofs with slopes of 0 25 in ft or greater are not. D dead load l live load l r live roof load w wind load s snow load e earthquake load r rainwater load or ice water load. Rain snow ice wind and earthrain snow ice wind and earth quake loadings are examples of environmental loads. Very slightly over time.

Words it varies with how the building is to be used. Ponding water accumulates on roof faster than it runs off thus increasing the roof 18 runs off thus increasing the roof loads. However if the attic is intended for storage the attic live load or some portion should also be considered for the design of. Minimum design live load can be found in asce 7 table 4 1 or ibc table 1607 1.

The live load on a roof is the weight of any temporary objects on the roof. Live loads l are a result of the occupancy of a structure. Roof and floor live loads are produced during maintenance by workers equipment and materials and during the life of the structure by movable objects such as planters and people. These loads are not considered to be per manent because of their inherent degree of variability with respect to time see the definition of loads in ibc 202.

Used but they typically defined the load cases or combination stress or strength limits and deflection limits. For example a storage room is much more likely to larger loads than is a residential bedroom. 2attic loads may be included in the floor live load but a 10 psf attic load is typically used only to size ceiling joists adequately for access purposes. Live loads roof live loads snow loads rain loads wind loads and earthquake loads are all examples of variable loads.

The nature of roof live load is different from that of floor live load so the approach to reducing roof live load is different from that used for floor live load. For example the live load for a room in a single family residence will be significantly smaller than the live load for an area of equal size at a movie theatre or sporting event. 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. How live load codes work.

Special examples of live loads. Load types loads used in design load equations are given letters by type.