AdvanTech subfloor size???

[TarMetto]

Really strange that this stuff comes 96" long but only 47.75 wide from edge to tongue?
I know it requires a 1/8" gap at all edges....but that's split between the sheets.
Our 20' x 40' build required a slight saw trim the 40' way...but would have ended up short
the 20' way had we not tested by laying 5 sheets down with proper spacing. the last sheet
actually landed shy of the rim joist.
Weird!

[Don_P]

Yup, it ticks me off. Without the rim (the boundary element) well connected to the floor diaphragm the floor does not behave correctly. If there is a deck ledgered onto the rim, that rim is not well attached to the house as is assumed, that is where those lateral deck restraints would be a good idea. If a row of blocking inside the rim will catch the sheets that is a good idea. The "solution" is to start with a row 16" or wider and finish with a row 16" or wider, basically buy an extra row of sheets. I use the cutoffs from that for stairs etc.

[MountainDon]

Or do like I did on our cabin... Instead of building a 16 foot wide floor I built a 15 foot 9 inch wide floor. Our length was 30 feet so I let that go and just cut off where the 8 foot length fell and used the cut offs for other odds 'n' ends.

[NathanS]

It got me on our house. Luckily at 20ft wide I was able to add 2x blocking to the rim so I could nail and glue the edge. We still added a ~1" narrow strip for the upstairs wall to sit on.. that was a pain. Ridiculous to undersize those sheets like that.

Do just want to add that I put that advantech through the ringer.. we are talking inches and inches of rain, some snow, and ice it saw for a few months. And not a single piece swelled anywhere.

[MushCreek]

I got caught, too, when I built my exactly 28' wide barn. I ended up cutting a 26" wide strip on each side, and re-purposing the considerable amount of scrap.