Partition Loads/Partition Allowances. 3

[connect2]

Some discussion with respect to 'Partitions' would be appreciated. All codes indicate that the dead loads of know permanent 'Partitions' should should be included and shown on drawings, makes sense. The confusion starts with statements of 'Partitions' being movable, or possibly relocated in the future eg. office spaces, fine got that, then a minimum 'Partition Allowance' shall be used, eg 20 psf uniformly distributed. Some codes treat partition allowances as live loads, some as dead loads. This 'Partition Allowance' can have a significant effect on seismic load calculations. How, when, and what types of buildings you utilize a 'Partition Allowance' for is the question. Thanks.

 

[JAE]

The 20 psf partition allowance in the IBC was a result, some years ago, of a concern that in a 50 psf office floor, the corridors, or exit-ways, that would normally require 100 psf live load would not be accounted for if the partiions were relocated.

Thus, they added the 20 psf to either account for the weight of partitions where they occur, or deal with added live load for exit-ways.

At least that was the concept..whether it makes sense, numerically or not is another matter.

The IBC 2006 has 15 psf listed in 1607.5 under "live loads" but uses the phrase: "provisions for partition weight shall be made" suggesting it is for the dead weight of the partitions.

Maybe the way to look at this is to consider a moveable partition as a truly LIVE load.

 

[OldPaperMaker]

In ASCE 7-05, Section 12.7.2 directs that the Effective Seismic Weight,W, of a structure shall include the total dead load and other loads listed below: (item #2 notes) "Where provisions 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 of floor area, whichever is greater."
I hope that this section helps answer the question.

 

[JAE]

Nice find OldPaperMaker.

 

[connect2]

I guess the crucks of this comes down to then;
3.0 Dead Loads, dead loads consist of the weight of ...built in Partitions ... 4.0 Live loads, 4.2.2 Provisions for Partitions .. In Office buildings or other buildings where partitions will be erected or rearranged, provisions for partitions shall be made .. (What I call a partition allowance). 9.5.3 or 9.5.5.2 effective seismic weight 'where an allowance for partition load is included in the floor design ..'
In apartments, hotels, and multifamily type occupancies, you are required to include the dead load of all permanent built-in partitions, eg fire separations between suites, partitons surrounding M/E clusters etc. along corridors. In my opinion these types of occupancies are not subject to a partition allowance and no provisions or allowances are required to me made with regrds to them. The limiting factor in these building types, re future use change of Occupancy is the live load of 40 psf.
Comments appreciated.

 

[WillisV]

Agreed...if you have a condo with set partitions, the partition weight can be included in the superimposed dead load, and as such should also be included in your seismic weight. If you have an office which can be easily re-arranged, you should use a 15psf partition LL for the gravity design, however per code you must then also use a minimum of 10psf allowance for the partitions in calculating your seismic weight.

 

[connect2]

anyways this was the thread I had started.