Cob buildings rock!

So I have recently (in light of the past Sustainability Day events) been reading about how to build a cob house. At the trade-show for Sustainability Day there was a booth with a couple from Victoria who are building their own cob house. I had heard about straw bale houses and was interested those, but I knew little of cob houses. So after talking with them I bought a book and now I am determined to build one for myself! I really like how they fit into the concepts of sustainability. They are built using only locally found geologic materials so that less carbon is spent trying to transport material from elsewhere. They are also made with materials that are not altered to any great degree and do not have any harsh chemical in them or required to make them.

Cob is generally made up of a mixture of sand, gravel, clay and straw which is then used to make the walls and compacted earth to make the floor. Now it still strikes me as weird that these walls made of cob can actually hold a roof up let alone a second floor, but they can and last much longer than a standard wood framed house. A wood framed house generally lasts ~50 years while a cob house if built properly can last over 100's of years! In the book they emphasize the importance of picking the right site (since you can't build cob in every environment) as well as looking at the environment surrounding it. They suggest making the plans of your house to incorporate the sunrise and angle of light that will hit the house during the different seasons. So you would have your morning sun room facing the east where the sun rises and have your kitchen facing the west where it sets. They also suggest limiting the windows on the north wall to make sure the cob walls have a chance to obtain the heat from the sun and release it slowly over the day into you home. Living roofs can be incorporated into the design, as well as rain catchment barrels and solar panels for electricity generation.

I still have more to read which I don't really have time for, but I hope one day I can build my own house...