Partition loads under IBC2006

[tedamiao]

I am a little confused regarding partition load for Residential house floors.
1. IBC2006 1607.5 clearly stated 15 psf for office buildings and in other buildings where partition locations are subject to change. Is this saying we have to consider 15 psf for nomal house wood floor?
2. This partition load will be live load, which means we do not need consider it for seismic weight calculation.

Am I right? Please let me know your guys' ideas. Thanks.

 

[Taro]

The partition allowance is used to design the floor framing in office buildings because the tenants usually change every few years. The new tenants often remodel the space and change the configuration of the interior walls. So the entire floor is designed with extra load so the walls can be relocated as desired.

This does not apply to houses. The wall locations rarely, if ever, change. If they do change, you may need to strengthen the floor at the new wall location.

A portion of the partition load must be included in the seismic analysis. Look in the earthquake section of the code where W, the effective seismic weight, is defined.

 

[tedamiao]

Thanks, Taro. We used to add 10 psf partition load to wood floor to give us around 20 PSF dead load for house design.

If no this partition load, floor dead load could be 10 psf only is no gypcrete or tile on floor. Sounds too small, isn't it?

 

[prsconsultant]

tedamiao:

Below is the reference section for partition loads for seismic mass calculations from ASCE 7-05.

12.7.2 Effective Seismic Weight. The effective seismic weight,W, of a structure shall include the total dead load and other loads listed below:

1. In areas used for storage, a minimum of 25 percent of the floor live load (floor live load in public garages and open parking structures need not be included).

2. Where provision for partitions is required by Section 4.2.2 in the floor load design, the actual partition weight or a minimum weight of 10 psf (0.48 kN/m2) of floor area, whichever is greater.

 

[tedamiao]

Thanks, prsconsultant, I checked ASCE7-05 and found this 10psf for seismic weight.

 

[msquared48]

If you really want to get picky, in the design of your next residence, try calculating the actual weight of the walls on each floor, interior and exterior, and dividing the total by the square footage. Compare that to ASCE7. Use the lesser of the two in the future as it will not vary much from house to house.

Mike McCann
McCann Engineering