Anatomy of a Petch Shower

For the start of this story, and if you want to comment on this, please read the May 21st blog entry.

Let me just say that now that I’ve done this, there are definitely things I would have done differently, if I had the chance to do it over. I guess that is one of the consequences of being iconoclastic, to put it politely. Stubborn and obstinate might be a less polite way to put it. Be that as it may, the floor is done and I think it will work.



The existing framing of the floor presented the first challenges. You can see I’ve numbered the joists. The faucet and shower head will be on the right in this picture. Joist number one presented the first problem. The wall just to the left of it is the “wet wall” I built. This meant I couldn’t really remove the sub floor there because this wall is no longer sitting directly over a joist. Also, because of all of the new plumbing, I couldn’t get a new joist under it. This would have been so much easier had I come up with the idea prior to building the bathroom, but there’s nothing I can do about that now, so let’s move on.

Joist number 2 and 3 are standard 2X10 joists. Joist number 3 ended up being the low point. Joists number 4 & 5 were at one time the exterior wall of the house. They sit on top of an 8X6 sill. Then there are the 3, 2X6 joists labeled as 6. These sit on a 4X6 that makes up the new exterior wall. This is a single story section of the house and they pushed the back wall out about a foot back in the 20s.



I shaved the joists to make the slope for the floor. Joist 3 became the low point and joist 4 was just trimmed down and abandoned. I added more of the 2X6 joists, and there is a new 4X6 support for joists 2 and 3. Joists 5 & 6, of course, sit on the 6X8, so they needed no extra support. Out of the picture there is another 4X6 support for joist 1 and the next joist to the left. The plumbing made it difficult to extend a single 4X6 to pick up all of the joists.

This small area of the house, right along that new wet wall, has a claw foot tub, 40 gallon water heater, washer, dryer, marble vanity, toilet, the cement floor under the tub, and all of the tile. The extra support might be over-kill, but as I said the other day, the floor was open and I had the lumber and piers laying around, so why not.



I then put the sub floor back in and I had the pre-slope, except for the one, 6-inch section at the far left. As it turns out it has a subtle slant to it in the right direction, but it would have been much better to include it in the shower area. I don’t think it will cause problems though, because when the shower spry hits to that area it will be completely contained in the tub. I mean, the last I checked water still runs down hill, so if a little water back there it should be ok.



I used an Oatey pan liner and drain for this. I thought the pan liner was going to be some high-tech polymer sheeting, but it’s just 40 mil PVC. Big whoop. I used both T-Rex polyurethane caulk and the 3M 5200 Marine Adhesive Caulk to install the liner. For the purpose of this discussion, I won’t really distinguish between the 2. I extended the pan liner all the way to the left and used the 3M 5200 Marine Adhesive to secure the liner and the piece of cement board. This would never be sufficient for a floor people would walk on, but once the tub is in place it will be impossible to walk on it. The tub will be centered in this area with 4 inches on all 4 sides between it and the tile. The liner extends a little ways under the cove of the tile and all seams where tile and liner meet are sealed with 3M 5200, as well. Oatly recommend the liner extend 2-inches up the wall, but that didn’t happen. All of the cement board in this area does sit 4-inches of the ground on top of redwood.



The faucet and tub drain presented the other problem. There is nothing you can do about the drain, but had I thought this through more I might have had the faucet supplies come out of the wall. To late for that. I cut the pan liner as best I could when I laid it in and then used a secondary piece with more of the 5200 to seal everything up. This will all get additional 5200 once the tile is set.



And finally today I laid the cement floor and created the final slop for the drain. The cement mix for this type of installation is very dry and sandy, and I found it very difficult to work with. I was supposed to use a screed (a long, flat piece of wood) to smooth it out and create the slope, but I found that very difficult as well. I think this is one of those things where this is what the pros use because they’ve been doing it for years and apprenticed under someone for years. I’m not a pro and I’m not going to master the art in one shot. I got out my plaster trowel and a straight edge, and along with level, I was able to get a smooth, even slope towards the drain. My slope is a little deeper on the right than on the left, but last time I checked water still runs down hill. I will be working with a much lower volume of water than a standard shower, so I hope it will be ok.

I’m sure if a professional tile setter saw what I was doing he would say I was nuts and this will never work. I don’t have a problem with that at all. They generally don’t get paid to try new things and I don’t really blame them. If something goes wrong then they will be called back to fix it. Why do one job that you’ve never tried before when there are 10 jobs where you can pound out the same shower stall you’ve done a hundred times before. So, we’ll see what happens. I’ve very excited about it. I think it’s going to work.