Step 7: Polyurethane
But I live in this house, as do my husband and 3 children, and that was not an option.
So I did some research and found MinWax water-based polyurethane for floors. I bought it at a local Duron paint store, rather than going back to the big hardware store, and it cost me $49.99 plus tax, rather than the $65 I'd seen it for online.
I cannot tell you how fantastic this stuff is! I researched online. I kept seeing reviews about how water-based polys bead up on oil-stained floors; and they cause the wood grain to come up; and you have to do SO many coats (one review said up to a dozen!!) for it to be done.
They were so wrong.
This stuff was great! It brushed on smooth and easy. There was no trouble at all with beading. It's a little milky going on, but they said it would dry clear, and it did. By the time I was half-done with the landing, the upper steps were dry to the touch. There was very little smell. I opened all the doors and windows in the house, and I left the central heating on this time, since I had a good 8 hours before the children would be home. (I used the disposable gloves for this step, too.)
On the landing, I used a lot of poly, and painted sideways across the boards first, to get plenty of poly into the cracks with the twine. Then I went over the wood again, painting with the grain.
I had read warnings about water-based poly drying too quickly, and brush marks being visible. I had even bought a small foam roller to run over it and take the brush marks out. I had no such problems. I painted it on with a brush, painting with the grain, starting at the edges and working toward the middle. Then I painted the front edge of the step, and then I used the roller brush to paint the underside of the lip of the step. It's the only thing I ended up using the foam for, and could really have used a $0.49 foam brush rather than a $5 foam roller. I tried the roller on the steps, but it left a textured look I didn't care for at all. Before moving down to the next step, I went over the whole step with the brush, just gently dragging it over the paint with the grain of the wood, including the front edge. The paintbrush only needs to be rinsed out with water to clean it, which was nice and easy.
It worked great and looks terrific.
I plan to use the same poly when I redo the dining room floor. It will be necessary to move quickly, so it doesn't dry on me, but it was so easy to do, with so little odor, that I'm not worried about it at all.
I let the poly dry for a solid 2 hours before doing the next coat. It was completely dry as I walked up the stairs in my socks. The only part not entirely dry was the gaps between the boards with the twine. Two coats look good, and the wood is sealed. The one gallon container easily did two coats, and could do a third, which I think I may go ahead and add on the next time I have some time off again. But I'm comfortable with it the way it is.
Again, the directions do say to sand in between, but I wasn't going for a smooth finish, so I didn't. I'm including here a picture of the texture I ended up with. It's nothing like my in-laws' unfinished staircase in their mountain cottage. There's just a very slight texture underfoot. If you didn't know to look for it, I don't think you'd really know the difference.