Been a creeper on here for some time but finally registered and this is my first post.
I recently bought a house with a few acres in Jamul, California. The lot is this decomposed granite and I am wondering if this stuff would be any good in a cob/adobe mix? If not what uses might it have for building purposes? I guess earthbags would be an idea but I like the cob better. If I cannot find a good clay source on the property where in SoCal is a good place to get clay?
It can be used for COB or anything you want. There should be some clay in it, do a jar and block test. If not add a natural polymer like lime, if that is not enough add some portland cement too or fly or wood ash. Rammed Earth take to it well I bet. I'd have a passive radon mitigation and be active ready.
Location: San Diego County, CA (9a) ~15-18"precip/yr
posted 2 years ago
I am building a cob house up in Ramona and getting clay from the land. I have seen people getting rid of soil from their property on craigslist and some of it looks to have decent clay content. You could try posting a want ad on there too.
Bringing this thread back from the dead. As a coincidence, I happen the be the third on this thread from Jamul. We have lots of decomposed granite here and my questions is would I need to mix it with anything other than 10% portland for a strong rammed earth wall. Would it need clay or sand? This seems like great material and I have a free unlimited supply.
You can't have everything. Where would you put it?