Subfloor Frustrations

First Floor Subfloor
Leveling joists
Leveling joists

I spent nearly all of this past weekend leveling the joists in the first floor. That effort was largely successful, with the nine remaining 12′ spans all adjusted to within a sixteenth of an inch using Method 3. I also leveled five other joists that required the tapered shimming method and got a few more sheets glued and screwed down. My hope, and in fact my expectation was that having done that I would then be able to start putting down full, 8′ sheets of OSB, allowing me to finally finish up this project.

Using the shimming method
Using the shimming method

Unfortunately, that hasn’t happened. In addition to not being level, the joists are not evenly spaced. They employ a generous “sixteen” inches on center alignment that means the 8′ sheets don’t line up in the middle of a joist at either end, sometimes coming short of one joist entirely. I tried planning ahead, measuring out to the next sheet and seeing if I could make one sheet stretch, but it just didn’t work. Instead I’m finding myself cutting sheets at roughly 32″, 48″, or 64″, plus or minus an inch or so.

Slow progress
Slow progress

On top of this, I’m finding that the walls aren’t exactly even either, so that I’m having difficulty getting the panels to align evenly down a joist and one panel to the next. After putting down an 8′ panel that left a gap at one corner and was snug at the other, I decided I needed to do better. As a result, instead of cutting my panels square at say 48″, I cut an edge that tapers back a ½” or so from the tongue to the groove, so that panels meet in the center of the joist and the tongues fits snugly into the grooves. This is precise and thus time consuming work. Tonight I spent two hours putting two small panels down, incrementally increasing the completed area by a whopping thirty-six square feet.

Cutting tapered ends
Cutting tapered ends

When I finished carefully scribing, cutting, and fitting the second of these panels I discovered that the joist was torqued and the shim I glued down was sticking up on the exposed side. Because of this, the second panel is raised up higher than the first. It’s a slight difference, but after the inordinate amount of time I’m spending to make everything level, it’s extremely frustrating. I’ll probably have to go back around with the power planer and even at least a few seams.

Argh! Not even!
Argh! Not even!

I keep reminding myself how I wanted to hire this project out, and thinking I really should have done that, high cost or no. At this point it’s starting to feel like it would have been worth it, assuming they would have done as good a job. It’s hard to even estimate at this point how long it will take me to finish. I’d like to think I’ve figured out my methods now and it should go faster, but who knows. The bay will bring its own set of challenges and I still have some of the shorter joist spans to level. After that I need to fill in the narrow, 5″ gap all along the North wall. Needless to say, I’m really looking forward to this project being done.

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