Alright, and another entry cross-posted from my own journal. Since there was interest in my strawbale post, I thought I'd share my real fascination, cob. Like bales, this can also be a very cheap building method and very durable:
So, last weekend we started working on the cob bench for natural building materials class. T'was great fun and I totally would love to build a house this way! In fact, I'd probably be out either working in the community garden or playing with cob right now if it weren't for the fact that it keeps raining. Ah well, I miss the rain and it makes everything smell good. Hopefully we get some more thunder, the lightning looks awesome over the mountains!
So, the day before the instructor and a couple friends with trucks went and picked up rocks to lay the foundation for the bench. The cob itself is made of clay soil, coarse river sand, and oat straw. I stopped off at the Farmer's Market (yay!) before heading over, so here's what it looked like when I got there:
Linda is filling in all the cracks and crevices with cob in this picture. It's amazing how much you can stuff into them!
At first we just glomped cob into the cracks, then we used these incredibly specialized and high-tech crevice tamping tools (okay, okay, wooden spoons from the Salvation Army in reality) to make everything really nice and solid.
Here's a really cool guy in the class that I forgot the name of mixing up a small batch of cob. We used three scoops of clay soil to five scoops of sand. It's a lot harder work than it looks too, the stuff is really heavy and you really have to stomp down to get it to mix, but it's a lot of fun too. We only had four people when we started...
But then we got more! After the sand and soil are mixed, we added handfulls of straws. The straw acts to reinforce the cob, kinda like rebar.
You stomp for a while, then as the mixture starts getting too spread over, you grab the tarp and flip it. You know it is getting mixed to the right degree when it starts rolling over on itself like a burrito when you are flipping it (will get a picture of that next time). When it's all mixed, you form it into "loaves", like bread to carry over. That batch was our biggest, so we formed a chain and tossed the loaves to eachother. I was too busy cob tossing to take pics, sorry, but it was a pretty cool sight I promise!
Here was our progress for the day. We would have kept going, but we ran out of sand. We got all the cracks filled in and we're now building up the top of the bench.
We were orginally going to making this bench on campus, but they rescinded permission at the last minute, so we are doing it in Linda's yard instead. Our instructor, Liberty, is also in an advanced sculpture class, so she's welding a funky roof to go over it, like a bus shelter, should look really cool. Speaking of other cool things in Linda's yard, I also really loved her pond:
- Music:Oko singing along to Mongolian ballads