Storage Live Load
Storage Live Load
(OP)
How is a "storage" room on an office building architectural plan usually loaded for design purposes? Table 4-1 in ASCE 7-02 requires 20 psf for "storage above ceilings" and "uninhabitable attics with storage" in residential dwellings. It also requires 125 psf for "light storage warehouses", and Table C4-1 suggests 80 psf for "nonresidential attic storage". My kneejerk reaction in the past has been to use 125. Does anyone else do the same, or use higher or lower?






RE: Storage Live Load
RE: Storage Live Load
If it designated "storage", I would go for at least 125 in that area, and maybe more. Frequently it doesn't start out as storage, but by the time the third or fourth tenant moves into the same space, things get moved around, and what was once open office is now the new storage area. Hence the "some-extra-just-in-case" design load, which sometiimes is enough to take care of the problem, and lets us tell the building owner "Oh, no problem, we figured on something like this from the start," which lets us be the heroes, if only for a minute!
RE: Storage Live Load
RE: Storage Live Load
The problem is, of course, that the designated room may move someday and a file cabinet area may appear in what would normally have been a cubicle city area.
We usually try to pin down the storage areas initially, making sure that the owner isn't intending on using dense file storage cabinets (200 to 300 psf).
Also, the floor system (say a deck and concrete floor) can and is usually designed to accept higher loads - look in some of the SDI tables and you will generally see numbers in the 100 to 400 psf range. If your deck can take locally high pressures, say from a group of heavy file cabinets, the overall joist or beam system can usually accept these smaller, high-load areas without overcoming the beam/joist capacities.
The problems come when a few years later the occupant puts in a library of high-stack books, an MRI unit, a dense file cabinet, or simply loads up a room with boxes of paper. That's when the strengthening is required.
250 psf storage, I believe, is intended for those higher stacked warehouse floors, not for 12' floor-to-floor situations in office buildings.
RE: Storage Live Load
- 3.0kPa for general office use (~ 63psf)
- 2.4kPa per meter of useable height for general storage (~ 15.3psf per foot of useable height)
- 4.0kPa per meter of useable height for stationary and packed-book storage (~ 26psf per foot of useable height)
- 4.0kPa per meter of useable height, but not less than 10.0kPa, for compactus-style file storage (~ 26psf per foot of useable height, but not less than 209psf)