Leveling joists and subfloor fasteners
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Replies
very rough floor framing..........
There are lots of ways to flatten a funky floor frame, your plan may work. Hopefully this rough sawn isn't green...
I can't say surely without being there to see more variables but my first thought would be to install the rims and shim/trim to a string line between them.
A lot of work.
I would install the 1" subfloor with 2.5" nails, preferably ring or screw shank then cover with tarpaper before the finish floor.
Rough sawn is green. Or fairly so at least. Milled about 6 weeks ago, from hemlock logs that have been down for around 4 years. Still pretty green though. Shrinkage?
Why use tarpaper if Im already using housewrap between the joists and subfloor?
wet may not mean green....
If the logs have been dead for 4 years they can't be "green", as in full of sap but they can still have a high moisture content.
Green lumber is still somewhat plastic and has a strong tendency to sag under it's own weight till dry when installed on edge as in a joist. Like maybe a 1/2" crown down in 12 feet. Real high moisture content maybe not so bad for that but both will shrink in width, a bit even in length. Not the end of the world though in any event.
If your subfloor is also rough 1" boards wet enough to shrink you can expect some rodent sized crawl ways to possibly form between the boards over time if the boards are very wide. Again not the end of the world.
I would not personally install the house wrap between the joists and subfloor at all. I would use tarpaper on top the subfloor and save the housewrap for the walls. Don't ask me for the science on that, I think it's because momma said "because I said to, that's why".
Subfloor screws and glue.
Level how you wish but shim solid, don't just stuff in cedar shims.
Glue the subfloor to the joists and use subfloor screws of the proper length and a stand up screw gun.
Nails are quicker and with ringshank, you should have no problem. Personally, I like screws. Both beat the heck out of air driven 8's.
Why shim solid and not cedar shims? What material classifies as solid?
Glue the subfloor with what? What might that product be called, and what is its function if nails/screws will be used?
Why shim solid and not cedar shims? What material classifies as solid?
Well, cedar shims can crush. If you stack 3/4" of them to fill a space, why not use a chunk of 3/4 plywood. For an ince, 2 pcs of 1/2...........I carry recycled blocks of ply and use them when setting cabinets etc. as cedar shims split, slip out etc when you stack them high. They have a use-mainly in setting jambs or fine tuning because of the wedge shape. Because they're called shims doesn't mean you use them exclusively. Blocks of solid 3/4 or 1-1/2 work also. I'm warry of using 3/4 pine as it is soft, sooner use plywood.
If shimming a beam-steel shims are the only thing allowed here. Again, because of the weight, you don't want it to crush. Joists, wood shims are fine-solid shims are better than fine.
Glue the subfloor with what? What might that product be called, and what is its function if nails/screws will be used?
Subfloor glue of course. I'd use PL Premium urethane adhesive-in both small and large tubes. The function is better holding power, fills voids and bridges gaps and in the case of PL Premium-it'll hold for near ever.