Improper subflooring installation

[mridgeelk]

I found this today in a crawlspace. The joists changed direction but the plywood didn't. According to the APA rating chart this reduces the strength by about 75%. There is a bamboo T&G floor installed (with no vapor barrier in the crawlspace). Does anyone know of a fix from the under side? The APA sent me a detail showing blocking 24"oc between the rim and the first joist that could be used throughout the floor. It shows nails through the flanges with no joist hangers. Has anyone seen this be effective? There is about 800 sf of plywood installed in this manner.

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[Jim Katen]

Originally posted by mridgeelk

I found this today in a crawlspace. The joists changed direction but the plywood didn't. According to the APA rating chart this reduces the strength by about 75%. There is a bamboo T&G floor installed (with no vapor barrier in the crawlspace). Does anyone know of a fix from the under side? The APA sent me a detail showing blocking 24"oc between the rim and the first joist that could be used throughout the floor. It shows nails through the flanges with no joist hangers. Has anyone seen this be effective? There is about 800 sf of plywood installed in this manor.

I can't imagine that you'd get very good support by nailing through the flanges, to say nothing about what the nails would do to the flanges. Before I'd even consider doing that, I'd want approval from the I-joist manufacturer.

I've stiffened up plywood floors by ripping sections of plywood (across the grain) to the same width as the space between the joists. Then I buttered them with construction adhesive and stitched them to the underside of the subfloor with screws. (Use screws that won't reach through the top of the subfloor.) The floor felt like a rock afterward.

- Jim Katen, Oregon

[mridgeelk]

Jim, that sounds like a better way than the blocking, the snag with that is that the staples used to install bamboo t&g protrude about 1/2". This is a new home built with no regard to manufacturer's instructions or to the concept of "done in a workmanlike manner". Many other issues, I think my client has backed out.

[Jim Katen]

Originally posted by mridgeelk

Jim, that sounds like a better way than the blocking, the snag with that is that the staples used to install bamboo t&g protrude about 1/2".

That's when you hand the $10/hr guy on the crew a pair of nippers and tell him to earn his keep.

- Jim Katen, Oregon

[Tom Raymond]

Just out of curiosity, aren't bamboo floors supposed to be installed the same as wood floors(perpendicular to the joists)? If so did the bamboo change directions or is it also installed the wrong way?

Tom