With strawbale I have to admit I have a love hate relationship. It made top 3 on my list however most of the people use it wrong. Except it’s initial price and extraordinary insulating properties everything works against it. It’s one of the riskiest materials to use. Strowbale might rotten easily, molds, mice will live in it. It’s final cost won’t be cheaper as a normal house. The overall insulation itself it’s better than normal houses but it’s far away from zero energy constructions. Strawbale itself it’s just a tool to use among various techniques and methods. Even hanging a picture on the wall can start destroying your walls. Strawbale has to breath all the time. If it can’t than it will rotten underneath. You can’t put furniture, tiles, shelves on your wall. Basically you can ‘t put nothing near the walls. The air has to circulate.
The bathroom and kitchen might be a real pain. Don’t use this walls here. Read about the air exchange. to see how we to solve this problem. Usually they cover the strawbale with 5-5 cm of clay on both sides to prevent fire. On the safety scale is one of the most safest materials. It won’t burn. Not even if you want to burn it. It’s compressed and the clay on it blocks air. If you somehow manage to burn a portion the fire won’t last. In that second that you don’t direct the fire source on it … it will stop to burn. In case you don’t extinguish the fire it might produce a small amount of smoke for days and weeks so you have to make sure it’s extinguished. Big flames won’t occur at all. I would use strawbale especially on those northern walls where I don’t have that much of glazing and doors. I would go even for a 70-100cm thick insulation with ease.
It’s cheap and it wort it … so why not? Read about the 30-30-30 rule here. If the building stands on pylons (in the air) and it has ventilated air below : than you might go with strawbale beneath the building itself. Personally I wouldn’t recommend it. I would rather use hempcrete or papercrete beneath the building. Making a false facade would increase the buildings life spam and insulation properties. In case of a strawbale I would change the 15-20cm niche to at least 1.5-3 meters. Ore even more. This place could be used like a garage, or deposit. A thin gabion wall would be an odd but quite good pairing with strawbale. It would keep the inner walls protected and the air could pass by with ease. Read about how to save big on plumbing & cables.