Tag: subfloor

Second Floor Demo Floor Demo

November 28, 2016 / / 2 Comments

Our demo party filled the first dumpster, so we swapped it for another one the same size and we filled it up too. In addition to all of the remaining plaster and lath debris, of which there was plenty, we took up the flooring down to the subfloor. This was an involved process, mostly because there wasn’t anywhere that had only one layer of flooring. The living room and dining room had a floated Pergo-style laminted pressboard floor that looked like hardwood. It, like most of the work done to the house shortly before we bought it, was cheap and installed badly. Despite being less than ten years old, it was in bad shape and we pitched it. Under that was peel-and-stick tiles, under that was a thin veneer hardwood, under that was the original hardwood floors, and under that was an inch-thick layer of plaster, mud, and general crud from when the house was built.

Under-floor Crud

As with the first floor, we didn’t save the hardwood floors. For one, there wasn’t enough of it. We’re completely changing the floor plan which would complicate any effort to save it, we’re installing radiant heated floors, and they were in really rough shape from all of the nails.

Bathroom floor removal in progress

Living room done, dining room in progress

Because our subfloor is planks that are spaced apart by a quarter inch or more, we couldn’t use a broom to sweep up all the debris without pushing cascades of crud through the cracks and down into the first floor where all of our stuff is in storage. Now granted, we covered everything with tarps and it’s all pretty dirty already anyway from the dust of the demo party and unavoidable debris that comes down anyway, including through various holes in the floors and walls. Even so, we wanted to do what we could to prevent it from being any worse than it had to be. Sarah spent several hours a day over the better part of two weeks sucking up all the crap with the shopvac. We hauled out about eight contractor bags of the stuff and filled our toters a few times, since the dumpster was gone.

Of course, then I went around de-nailing studs and joists and leaving nails and random other bits of crud all over the floors she had just vacuumed, but this is kind of how it goes. I’ll get it cleaned up again after we’ve pulled out the rest of the interior walls and the plumbing and are ready to start putting things back together. It’s already starting to look like the kind of space we can start building things in, but it will really start looking promising once we get the whole floor completely cleared out.

Landing Subfloor

August 21, 2014 / / 1 Comment

Normally I wouldn’t dedicate a whole post to a little section of subfloor, but the landing turned out to be a bit involved. When I started building the and fitting the stringers I realized that the landing was wonky. It was ¼” too tall and it wasn’t square. To compensate for being too tall, I decided to use half-inch plywood subfloor instead of ¾” OSB. However, ½” is pretty thin for subfloor, so I devised a scheme for fitting sections of ¾” OSB in between the framing members, glued to the underside of the plywood (and to the framing) to add strength and thickness.

Test fitting OSB

Test fitting OSB

If the landing had not been out of square, this would have been pretty straightforward: just cut some rectangles to fit and done deal. However, given the out of squareness, everything was parallelograms. I’ve learned not to measure things any more than I have to. Measuring introduces more inaccuracy than it eliminates. Instead I put the OSB on top of the opening (generally lining up one edge) and drew the shape from below. Then I cut it out along the lines with the circular saw and fit it into place.

It worked fairly well, though I discovered after I had glued and screwed down the plywood (though thankfully not before it had dried) that one piece that fit between the stair stringers would not fit in from below because I sistered 2x4s to the stringers. I had to unscrew the corner of the plywood on top and slide it in (actually I had to do this three times because it kept falling through). Finally, once everything was in place and the glue was setting, I put in about 7,000 screws.

Landing subfloor installed

Landing subfloor installed

In one section the OSB was squeaking when I walked on the landing. I considered that it might go away once the glue set, but rather than take the chance I used a long 2×4 to press the underside of the OSB up against the subfloor and tightened all the screws. I left it that way until the glue set and now it’s all feeling solid and squeak-free. With this done I can work on the second run of stairs up to the second floor.

Basement Stairwell Framing

March 28, 2014 / / 0 Comments

The subfloor is nearly done. I just have to put down a thin, 4″ strip along the North wall. However, before I can finish that up I needed to fix the stair opening to the basement along the outside wall. When Matt B and I framed it last year, we cut back the joist ends along the outside wall. Now, as with all of the other joists, they need to be at the right level. I took a look at it and decided it would be easier to pull out the joist ends and redo them.

Stair opening

Stair opening (also pictured: giant rack of old floor boards in basement)

I first tried cutting the joist ends down to the right size, but they were not in great shape, and a couple of them broke in half. I tried cutting some new pieces but nominal 2x10s are too loose in the rough sawn notches and I couldn’t position them as accurately as I wanted. In addition, I decided I wanted some sort of bracing down the length. A full 2×10 would close up the cavity and prevent it from being spray-foamed. Notching a 2×4 into the ends would work, but would be a real pain.

Instead I decided to just put new 2x4s (planed a few times) on top of the rim on the other side of the wall studs, screw a 2×4 onto the face, and then for good measure, shore it up with some support blocking glued and screwed underneath.

New framing, start of subfloor

New framing, start of subfloor

With the new structure built, I started working on covering it in subfloor. I wanted the OSB to span the opening, which required some fancy carpentry. The narrow section along the wall needed a groove because the rest of the subfloor is tongue and groove. I’ve been cutting my own grooves out of my leftovers on the table saw instead of wasting full panels. The problem here is that the piece is shaped like an ‘L’, so cutting the groove on the inside edge was complicated by the fact that I couldn’t slide it all the way across the table saw.

I started by cutting the groove as far as I could on the table saw, which left about a foot or so. Then I used my circular saw to get closer, leaving about 4″. Finally I used my oscillating tool to cut the sides of the groove and a wood chisel to finish it up. The piece slid in and fit like a glove, tying this section in with the rest of the subfloor. Once I finish this edge, I just need to plane and glue some seams and this project will finally be done!

Learning Lessons

March 21, 2014 / / 2 Comments

It goes without saying that in a project like this, having never done anything like it before, that we’re going to make mistakes. As they say, the important thing about making mistakes is what we learn from them. I’m trying to learn from what we’ve done so far, both to help inform us on how to do things in the future, but also just as advice to anyone thinking about doing the same types of things.

Fortunately, most of the things that I would do differently have been small: I would use the “Q” column caps with the “SDS” screws for the LVL beam so I didn’t have the stupid through-bolts sticking out. Drilling those bolt holes was an unbelievable pain and furring and drywalling over them will suck. I would have checked for square when re-framing the bay, and done the rigid foam around the bay differently, since I’m not thrilled with the angled corners. However, these are small enough things that I don’t worry about them too much.

The damn subfloor, though. No project has offered so much “learning” as this. If I could go back in time, the steel beam in the basement needed to be about ¾” higher than we put it. When I was jacking up the old beam, I ran into a lot of resistance trying to get it any higher so I made it level where it was. If we had gotten it up a bit higher, the whole joist leveling project would have been considerably easier. Failing that, I needed to shim under all of the joists at the beam (Method 3). I should have held off making the stair opening down to the basement until the leveling was done. I should have brought all of the OSB in right away instead of letting it sit outside under a tarp all winter.

OSB in the snow

OSB in the snow

I needed to plan out the subfloor courses first, since the joists aren’t exactly 16″ on center. I needed to put down chalk lines for each course instead of assuming the outside wall was reasonably straight, or at least use the laser. I should have taken up all of the old floor right away, instead of a section at a time. That way I could have repositioned the joists that were just a bit off in the middle by using blocking. I should have checked the joists for being out of square, so I could plane down high edges.

I should have ripped the tongue off the first course and left the groove exposed instead of putting the groove against the wall and leaving the tongue exposed. Jamming the groove over the tongue when it’s already screwed down is a bad way to do it.  I needed to put glue into the groove before putting the next panel in.

Slow progress

Subfloor

More than anything else, though, I should have hired it out. It would have cost thousands of dollars, but it would be finished by now, probably a couple of months ago. Instead the subfloor isn’t finished, it’s not done as well as it could have been, and most likely we won’t finish the first floor this year as a result. Well, lesson learned. I’ll definitely be hiring out some things going forward to try and get this project back on track.

Bay Leveling

February 27, 2014 / / 3 Comments
Removing floor boards

Removing floor boards

The pre-subfloor leveling isn’t quite done yet, and the bay window on the front of the house brought its own set of challenges. For starters, the joist running across the very front of the house (and across the widest part of the bay) is embedded in brick, meaning I couldn’t jack it up the way I did most of the others. There’s also a gap of nearly two feet between that joist and the joist in the center of the bay, which is considerably wider than the 16″ that most of the joists are spaced. Finally, the old floorboards rested directly on top of the brick foundation and extended under the bay walls, whereas in most of the balloon-framed house, it only reaches the edge of the wall.

Level? ish?

Level? ish?

When we rebuilt the bay windows, I noticed the floorboard situation and debated replacing it then, but between doing only one window at a time and the corner studs not being replaced, I decided against it. That meant the first step was to use an oscillating multi tool to cut the floorboards back at the wall edge. Then I glued shims to the top of the existing joists and added some blocking joists to better support the gap between joists.

Shimmed, Reinforced, Re-mortared

Shimmed, Reinforced, Re-mortared

Questions sprang to mind of how to control air and vapor infiltration through the foundation and through the gaps in the wood, and how to insulate the bay properly. We’ll be spray-foaming the cavities in the wall, and on the sides of the house we’ll spray foam the top of the foundation wall to air seal it to the wood, but here that isn’t an option because the brick comes all the way up to the underside of the floor. The exterior rigid insulation doesn’t help either because it doesn’t extend over the brick.

Front shim and spray foam

Front shim and spray foam

I decided to attach an inch-thick shim to the inside edge of the brick wall (on top of sill gasket) that will support the subfloor. In front of the shim, and along the top of the brick on the sides of the bay, we’ll fill with spray foam. I’ll also glue the outside edges of the subfloor to the framing to further seal everything. Hopefully that will be sufficient, since it will be damn difficult to do anything about it with the subfloor in place.

When I initially test fit the shim I realized that the brick was —perhaps unsurprisingly— uneven. In order to properly support the shim I had to mix up some mortar and straighten out the top of the foundation. That meant waiting a couple of days for the mortar to set up, but then I was able to drill some holes into the brick and secure the shim with Tapcon screws.

First piece of OSB

First piece of OSB

I went through a few cans of “big gap” Great Stuff, since the real spray foam won’t be for a bit. Fortunately it’s so cold that it cures slowly, giving me ample time to even it out. I got the first of three pieces of OSB down that go into the bay. I took my time and worked out the dimensions exactly, accounting for all of the unevenness of the studs. There’s still a small gap along the edge of the angle, but I’ll fill that with caulk. The important part is it’s secure, level, and insulated. I’m considering whether I should exchange the one piece of blocking in the center with two, since that would be a more proper 16″ spacing, plus there’s a good chance I’ll wind up putting an electrical outlet in the floor there. One of the reasons to use screws instead of nails is you can change your mind without too much hassle.