wrote in message
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| question on trusses. contractor is building a stand-alone garage
| 24'x30'. 2nd floor is for storage. he's using 2x8 lumber for the floor
| joists, mated in the middle with a gusset plate.
|
| is this sufficient for bearing weight on the 2nd floor for storage?
| some reason I thought wood-composite i-beams were better. he said the
| gusset-type should be fine.
|
| yes? no? opinions?
|

rip it out and do it the right way.
floors can NOT have splices or nailers in them.
24 ft span...........2x8......................under sized for storage.
TJI's would work best......................1 piece.............no
joints.

or add a strong back to the top of the spliced joists.

Cindy Boucher wrote:

24 ft span... 2x8...

With a perfect splice, S = bd^2/6 = 1.5x7.25^2/6 = 13.1 in^3 and
M = fS = 13100 in-lb and W = 8M/L = 8x13100/(12x24) = 365 pounds
of total load, ie 15.2 pounds per linear foot or 11.4 psf on 16"
centers, if I did that right.

So maybe we need more than a perfect splice, eg a kingpost
or a truss or a wall under the middle.

Nick