Since we rent the house, there wasn’t an option of tearing out a bathroom and redoing it, so the next best option was to make a bathtub for outside. What I ended up making was out of solid California redwood, and we are able to fill it with hot water with a hose adaptor to our shower, which is just inside the door from our garden. I had a lot of choices - do I make it like a barrel, with coopered sides, and a metal ring holding it all together? I did an awful lot of research for this project, and that seems like the most common solution, especially cedar hot tubs from the 70’s, and also water towers. . Structurally, it makes a lot of sense, but to make one big enough to really lay down in like a proper bathtub it would have to be enormous, and it would require tools I wouldn't have much use for after this project.
What I preferred is something like that makers in Japan call an oforu. Here is one example that costs over $10,000, and a build video that’s only in Japanese. I learned that in Japan they are traditionally kept in a tiled room with a drain in the middle of the floor - so they are ‘supposed’ to leak a bit. Seemed like a good fit.
It was a gamble in a lot of ways - a pretty ambitious project in at least the sense that if it didn’t work, it felt like it would fail in the worst way - just split down the middle, leak water, or worse. I never did the math on how much the water weighs and if the sides could support it.
Luckily, with a lot of careful planning I did make it work. A lot of the project plans were changing constantly or in my head, so I didn’t work on one strict plan. But I’ll try to document what I did along the way.
The first step was getting the lumber. I had done some rough math and spent a few months studying how other redwood tubs went together, and had a pretty good idea of how I was going to build mine.
Starting with a top grade redwood was the first step. Luckily, Big Creek Lumber was a source of sustainably sourced, kiln dried, really clear stock. I loaded up my Subaru with 8ft long 2x6’s. By my original math I was going to have four extra, but I ended up with none left when I was finally done. Always buy extra!
This wasn’t all of it!
I got them stacked up in the back of my house and stickered to start. I probably spent two hours going through all the board I could, looking for ones that were pretty dry, and as clear of knots or holes as possible. Some of them still needed to dry a bit more, so by properly sticking them I gave them a chance.
The next thing I had to do, which I had learned the hard way from another piece, is to plane down the edges. I usually try to use only hand tools, but this was a good project to test what I could do with machines, since it was just so much wood and so large. I spent about four hours running all the boards through the planer, very slowly.
The next step is going to be jointing the boards together, so I had to get them as good as possible.
Here’s the revised plan for how I was going to use my lumber. In December I went to New York City and stayed in a hotel with a fabulous bathtub, big enough for two people, and I decided to use up all the ‘extra’ wood I could to maximize the width. Good thing I bought it.
Coming up next: milling the lumber