15 PSF Partition Load - Part of Lo In Live Load Reduction...?

[walterbrennan]

It seems clear that the 15 psf partition load, as required in IBC 2015 section 1607.5 is considered a live load... at least, the commentary appears to present it that way, when it states, "This partition allowance is included under live loads..."

--- What's less clear is whether or not this live load should be lumped together with the ordinary occupancy live load (e.g. office) BEFORE the live load reduction factor is applied, or AFTERWARD.

A quick look at the live load reduction provisions in section 1607.10 yields the following: "Except for uniform live loads at roofs, all other minimum uniformly distributed live loads, Lo, in Table 1607.1 are permitted to be reduced..."

--- Without seeking to be legalistic, it is probably worth noting that the partition load is not, in fact listed "in Table 1607.1"

I'm not seeking to instigate an argument, based strictly on logic, opinion, dogmatic past experience, etc. Rather, what I'm seeking is an actual published opinion, from a trustworthy source (e.g. ICC, ASCE, etc.) which might provide clear direction on whether or not the 15 psf partition load was ever intended to be included in Lo.

Can anyone offer any such reference...?

 

[rapt]

JAE,

Your point 2 is an interesting one I keep emphasizing.

The code defined loadings are the MINIMUM design loads you should use. The clients requirements set the actual design loading. And thr pattern of that loading.

If the loading expected for a specific member is larger, then it is the designers responsibility to use the larger load, even if it is a building of the same general usage type.

If that higher load is known to be able to be applied to the whole floor system at the same time, or to the full slab area contributing to a single member, then no live reduction is allowed, as the designer knows that every member in the floor will receive the full loading.

The same as deflection requirements are the highest allowed. Specific situations may require tighter deflection limits, especially curtain walls and partitions for which the manufacturer defines deflection limits. And if a manufacturer puts in a much cheaper price, you can bet he wants tighter deflection control, as allowing for more deflection costs a lot of money.