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Sat, Apr 2
8:00 am

Plumbing a Straw Bale House: Today I wanted to talk about plumbing a straw bale house. Water is a big enemy of straw bale houses. I usually hike on Saturdays and blog Sunday mornings, but last night my cat Alien was bit by a rattlesnake.

For those of you who have read the book, this is the same kitty who showed up at the wall-raising. He is now a large, strong, very handsome Maine Coon who rules the house (and the mice that venture onto the porch). I'm just here to open the door, dish out catfood and get the fur off the furniture. Last night, he came in with a swollen paw, making growly noises, and I thought he had sprained it. We have a vet in the area who is open evenings, so I took him over there and as they shaved his paw, we saw four fang marks, two bites, inside his front paw. He got anti-venom last night and I am waiting for a call from the vet to tell me I can pick him up this morning. He's 11 years old now and one tough kitty, so I'm sure he'll be fine.

So, back on the topic of plumbing. Straw bales can handle water that gets on the outside of a bale and has a chance to dry off. But you don't want water to get to the interior of a bale and stay there, with any chance of turning to mildew or mold. Straw disintegrates into black powder if it mildews. I live in a dry climate, so I don't have to worry about water that might splash onto the bales from the outside - it will dry off quickly. Our humidity is often below 10 percent. But since we need to plumb a house and plumbing brings a chance of water leaking, we have to be careful on plumbing choices.

One solution is to plumb through the floor. I know many people do that. The solution that I used and was recommended by Jon Ruez, is Pex plumbing. This is the type of plumbing that has been used for radiant heated floors for quite awhile and it is becoming more common as a means of regular plumbing. It consists of a manifold with hot on one side and cold on the other, then many valves to which you attach thick plastic tubing. The tubing goes all the way to its outlet - a faucet, shower or wherever you need water, so there are no joints in the walls. Joints are where you get leaks. Also, we ran most of the tubing above the walls, along the top of the roof plate, to get across the house. Then, we only had to run it down the wall to the fixture.

Here is a picture of the pex manifold. The blue valves are cold and we labeled each one with the name of the faucet to which it goes. You can barely see the other side with red valves - that's the hot side. The big blue thing is from the days when I had a hot water heater and needed an expansion tank in case the water over-heated. I now have tankless and solar discussed in March 13 blog. A couple things I like about this type of plumbing are that it was incredibly easy. Without joints, we just ran the tubing across the house, securing it every four feet. We didn't have to measure to each corner, put in a joint, etc. Also, I can easily turn off the water to any faucet, if needed (well, sort of - see below).

One thing that makes Pex difficult is that you need a special crimping tool to secure the fasteners at each end of the tubing. The tool is expensive to buy or rent. Maybe that has improved over the years, but I still think it's worth it. The joints on this manifold are made of plastic and they break too easily, also. Many of them have not been moved in the ten years since I built the house and they are pretty stuck now. I hope Pex has improved their manifolds. But I still think it's a great plumbing system.

If you have other questions (my kitty came through fine) - send me an email -

Keep it Simple - and be kind!