Roof Live Load Reduction Example

For uses other than storage where approved additional live load reductions shall be permitted where shown by the registered design professional that a rational approach has been used and that such.

Roof live load reduction example.

Loads should be determined in accordance with this chapter. 1 2d 1 0e l 0 2s when h loads are present they shall have 6. R 1 1 for a t less than or equal to 200 psf r 1 1 2 0 001 a t for between 200 psf and 600 psf. Building codes permit reductions in the standard l 0 design live loads when the influence area ai k lla t is larger than 400 ft2 37 2 m2 as given in the following formulas.

If your structure has a sloped or flat roof you still need to calculate the flat roof snow load. The requirement is presented in asce 7 05 4 9. Roof live load reduction. 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.

Minimum design loads for buildings and other structures location uniform load psf. However if the attic is intended for storage the attic live load or some portion should also be considered for the design of. Where snow isn t a problem the live load can come from people working on the roof and any equipment they. 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.

Where l r shall not be less than 12 psf and not more than 20 psf. Roof live load reduction. Building live load reduction recognizing that the probability of supporting a large fully loaded tributary area is small. L r l o r 1 r 2.

Where d is floor dead load. Roof live load may be reduced by the following equation. After you obtain the roof slope factor from those sections in asce 7 10 the balanced design snow load for the sloped roof can easily be calculated using equation 7 4 1. 0 9d 1 0w a load factor of 1 6 when adding to load 7.

The live loads for members supporting two or more floors are permitted to be reduced by a maximum of 20 percent but the live load shall not be less than l as calculated in section 1607 10 1. Minimum uniformly distributed live loads adapted from sei asce 7 10. 0 9d 1 0e effect or 0 9 when resisting the load when permanent.