I’m sure there’ll be a whole lot of these posts, but here’s a couple of things I learned from working with backer board and thinset:

1. If you’re using HardieBacker cement board, don’t use generic cement board screws. Make sure to buy the green-coated square-drive HardieBacker brand screws. With the 80-year-old framing in our house, driving one of the generic screws went like grr umph argh oh hell that’s good enough whew that’s one; whereas driving the HardieBacker screws went like zip ZARCH zip ZARCH zip ZARCH.

2. Don’t mix thinset with your bare hands, no matter how expedient it seems to be at the time. Last night I was cementing down the backer board sheets to the bathroom floor, and at first I mixed up what I thought was half the 50-pound bag but only turned out to be about a third of it. That was easy — the drill + mixing paddle seemed to be able to handle it, and hand mixing with a brick trowel wasn’t too hard. But it only put down one and a half sheets.

So I went to mix up the rest and it didn’t want to mix — I put down my drill when I noticed literal smoke coming out of the motor housing, and still there were huge dry clumps at the bottom that the brick trowel wasn’t breaking up. So I just stuck both hands in and kneaded it like the world’s thickest cookie dough, and then washed my hands off under the hose immediately afterwards.

About two hours later, as I was thinsetting the joints, I noticed that my hands felt sticky, like there was a thin layer of rubber or silicone on them. When I finished all the jointing and cleanup at 12:45am, I realized that, no, in fact, it was the skin on my hands that was peeling.

Basically, it appears that the entire top one or two layers of epidermis on my fingers and palms got killed by the thinset and is peeling off. Ick. You can kinda see it in this photo:


I guess this is my first remodeling “injury” — so far hardware stores have been more dangerous than the actual work, as I bash into wire racks sticking out into the aisle and so forth.