Apartment Design Loads - Flat Metal-Plated Wood Trusses

[DCEngr1]

Wood Truss Engineers,

Normally, is there an additional dead load for non-bearing interior stud walls put in design loads for an apartment-use floor structure using metal-plated flat wood trusses from framing? I have a 40 (TC - LIVE), 15 (BC - DEAD), 5 (BC - DEAD) load compilation listed on a truss drawing that I am looking at. If the partitions between rooms are not intended to support the ceiling or another floor above, do you need to add a load to account for the weight of the partitions, or is that load considered part of the live load along with cabinets, furniture, etc.?

Thank you for your assistance.

DCEngr1

 

[dcarr82775]

I specify a dead load that includes an allowance for the partitions. How much varies per the project. I know others who consider it covered by the 40 psf LL. IMHO, the partitions are not part of the LL and should not be counted as such.

 

[manstrom]

If you read that section in the code, it requires a 10 psf load for "movable" partitions. Non bearing walls don't qualify as movable, so it is up to the designer.

Take a representative unit, add up the non bearing wall weight and average it over the area of the unit. You can also realistically subtract out the live load at that area. It may also fall into the "misc" category that you include in your loads.

I usually use 25 psf DL for residential units with gypcrete.

When I am working on a problem, I never think about beauty but when I have finished, if the solution is not beautiful, I know it is wrong.

-R. Buckminster Fuller

 

[Signious]

Mirroring what others have said, it just comes down to a design decision.

I am usually more concerned about making sure the truss design/supplier is upping the DL around kitchens, laundry rooms, and wet bars. Anywhere your going to have a bunch of heavy appliances and or granite counters.

Another commonly missed DL in stacked multi-family buildings is all the extra gypsum & material weight on the floor fire assembly. 25psf total DL is what I typically call for on a 16-24" deep parallel chord wood truss w/ 3 layers of gyp, mechanical equipment in the platform, and spray foam.

 

[DCEngr1]

Responders . . . Thank you for your assistance. I appreciate you time & the information.

 

[XR250]

I usually just add 10 psf. I never come close to sizing these things for minimum serviceability requirements anyway so it probably is not necessary.