I'm beginning the process of really starting to get informed about the details about what would be involved in building an earthship and wanted to clear up two questions i had.
1. in the global earthship, what is the thickness of the foam board used to insulate the earth around the tires outside the home.
2. My build site has no well and I'd love to be able to catch all our water using the roof. The part that doesn't make sense is the math. Mike stated in a video that the earthships they built at their site could gather plenty of water to support the family size on their 7-8" of water per year. He also stated that the water guy in their county figured that the average american uses 90 gallons per day but due to the recycling of water in an earthship they only used 19 gallons per person per day. In a place of 8" of water per day that means for each family member there needs to be 1486sqft of roof! For my family of 4 it would require a 6000sqft house in an area of 8". Math doesn't add up, very possible i'm figuring something wrong but i wanted to check in with you guys. In my case i live in a place with around 13" of rain and a few feet of snow per year (so maybe another 2 inches max), but still math doesn't add up, at 15" of precipitation we're looking at a bare minimum of 3200sqft of roof space for a family of four assuming we get the full 15" every year? just seems excessive.
Well that's all for now. Truth is i have tons of questions but figure I'd ease into it. The jist of my idea is to build an earthship type house but using ecology blocks instead of tires (to save on time and labor as I'm self employed and every hour i spend on the house is an hour i spend not earning a living). I live in North central washington at 4000ft where temps drop down belowing freezing all winter and only go up to around 80F during the heat of summer.
