How To Tile a Bathroom Floor

The right way:

1. Hire a tile crew
2. Sit back and drink iced tea
3. Pay the nice people when they leave.

The way Kathy and Jim do it:

1. Buy some Sunset how-to books*
2. Make several trips to tiles stores and Home Deport
3. Wait for hot weather
4. Kneel on the floor for 10-12 days
5. Get clothes dirty 
6. Make several more trips
7. Groan about aches and pains
8. Admire handiwork

 *Sunset Publishing Co.: "The triumph of ambition over incompetence, for over 50 years."

I'll get straight to the chase: Kathy and I spent the last two days tiling our upstairs bathroom, and it looks pretty darned good. If you ever want to do this kind of thing yourself, here's what we learned.

The first step was to make sure the underlying redwood was in solid condition, and it was. We had to scrape off a lot of old adhesive and goo from the previous carpet (and the tile before that), but eventually it was flat and clean.

Next, you want to eliminate all the squeaks. Bounce around the room in your socks looking for squeaky floorboards and screw 'em all down. You can sometimes sprinkle talcum powder between the boards to silence squeaks, but that's just a temporary fix. You really want to drive long screws through the floor and down into the joists. That means finding the joists, which can be tricky. But if you're covering up the floor with tile anyway, you can drill all the holes you want until you find the right spacing.

When the floor is solid and silent, put down Hardie Backer cement board with a combination of adhesive (mastic) and more screws. Hardie makes special screws for this (naturally) with heads that lie flat and won't split the backer board. Don't worry about butting the boards right up next to each other. You're just supporting the tile to come, not making a pretty floor. Small gaps between seams don't matter. Tape over the seams with mesh tape and more mastic.

Now you're ready to lay tile. Or are you? What you don't want to do is starting laying your tile along the edge of the room, working toward the opposite wall. I know that seems logical, but it's wrong. You'll wind up with a roomful of slightly out-of-kilter tile and wonder why.

What you really want to do is measure the entire room very accurately. Don't round off the numbers or assume that two walls are the same. Measure everything and measure it exactly. If a wall is 68 and 7/8" then write that down; don't round up to 69 inches. Mark all the dimensions down in a notebook, paying special attention to small obstacles like plumbing, outlets, uneven studs, or whatever.

Also don't assume that your walls meet at right angles (ours certainly don't). Dust off your old high school geometry texts and relearn how to find an angle. Measure the four walls, then draw diagonals from the corners to the opposite corners and measure those. Are they the same? If they are, you're square. If not, you'll have to accommodate the out-of-square room when you start laying tile. (You'll also know where the exact center of your room is.)

Our room gets slightly narrower at one end. You can't see it, but the measuring tape says it's definitely there. That means we had to align the tiles in such a way that you won't see them "creeping" away from one wall or toward another. The tile should always look straight, even if the room isn't.

The best way to accomplish this is to pretend you're going to start laying tile from the door, but actually start laying it from the opposite side of the room, working toward the door. In other words, the doorway is the most important spot and should look the best, so start your measurements from there. You want full, uncut tiles in the doorway because that's the first thing everyone will see. But you actually want to lay the tile starting from the far side of the room, and that means taking very careful measurements so that when you finish, you wind up with perfect, uncut, straight tiles right in front of the door. Easier said than done, I know.

Decide which direction is perpendicular to your doorway and snap a straight chalk line along that dimension, which may not be exactly parallel to any of the side walls. This line will be your starting point. It might be near one of the walls, or it might be right down the middle of the room; it doesn't matter. What matters is that you believe it, trust in it, and respect it. That line is your beacon, your guide. You're going to line up your tiles to that line, not to the walls. Measure as many times as you have to until you can completely trust your chalk line.

Now you can start getting dirty. Smear thinset and trowel it out as thick as the tile maker says. Generally, the bigger the tiles the thicker you want your thinset. Always trowel your grooves in the same direction; don't make swirly patterns. This allows the goop to spread evenly and avoids trapping air bubbles. It's also good discipline. Think of it as a Zen rock garden.

By the way, trowels are right-handed. It's a nuisance to hold a trowel in your left hand, but it's just one of the crosses we bear. (sigh)