Recently I have viewed some interesting sites about using rice hulls for insulation. They are a throw-away and as insulation, perform as well as fiberglas insulation at as little as 1/5 the cost, depending on transportation costs. http://www.axwoodfarm.com/PAHS/RiceHulls.html
I plan to try these as wall insulation in the low 3' walls of the GH I hope to build this summer, and from there... who knows?
Great article darius. Interesting especially since I just saw an add for rice hulls in my MNLA magazine before I got on line. Anybody used rice hulls for mulch out there? I'm thinking they would probably not be good in windy areas. I never imagined you couls use them as insulation. I love this new forum, so much interesting stuff out there!
You can also use denim as insulation that is waterproof and mold proof from what I have heard. BUT they cost more than fiberglass. We checked it out 2 yrs ago for my grandma's house but it was way too much. That is interesting about the rice hulls. Let us know if you do it and how it works out.
spot... I had thought about rice hulls for mulch... and then I thought, "Hey, they are 20% silica (sand)" and when they break down in my clay soil, will I have cement? LOL.
pepper, one thing that interests me about insulating with rice hulls is that they don't settle. Like your denim, they don't mold either. I'd worry about any fabric in a wall cavity being a fire hazard.
At work we get rice hulls to test. I end up taking the samples home and put them in my compost bin.
I've never heard of rice hulls for insulation before. I do know in terms of feed, rice hulls can be a cheep, but I don't know. I think it will take a few years before I could seriously insulate any walls though as our samples are quart size! LOL
We tried it for awhile but we produce too many scraps too fast. We would need a couple more buckets and more patience to let it sit before diggin a hole (yes, actual work) for the fermenting product. Not stinky at all though.
I bought one Happy Farmer bucket and then have been using regular 5 gallon buckets with lids. I can fill a 5 gallon bucket with kitchen scraps in about 5 days. Some goes into the worm bin (Wriggly Wranch), some goes into a bokashi bucket and the rest goes into the BioStack at the community garden.
The first time I buried the Bokashi, I witnessed earthworms "running" across the surface of the soil and then diving into the spot where I buried it. They really love the stuff.
I would like to use rice hulls for insulation if I could find a source for it. My garage is unfinished on the inside. My rabbit stays there in the winter and it gets really cold for him. thinking about plastic bags of rice hulls, used sand bag style between the studs. tack screen molding across the studs to keep the bags in place. Guess I could use packing peanuts, also.
Rice hulls will insulate better. I'd think about some kind of screen or hardware cloth across the studs and loose insulation inside the cavity. AL isw one of the top rice producing states so I'd think you could find rice hulls with some effort. Good luck! and let us know what you do...