Over the years quite a few people have asked us for advice about the hut module that we built and lived in for five years. I will attempt to provide some answers for the most common queries:
First of all, it is a great idea to tackle a smaller project before committing to a huge house. We, as non-builders, gained invaluable experience, confidence and knowledge with this little project. It also gave us a place to live on-site as we worked on the big house for five years. This was good.
Our hut is five metres in diameter. We dug it in to the ground as far as we could but I would most certainly not do that again on our block. You really need to have rock-free, well drained soil to dig in. Apart from the back breaking work of sledge hammering boulders, we have always had a bit of damp on our below-ground level wall surfaces, which would be a royal pain in the bum if the walls were plastered, painted and susceptible to bubbling, but as they are mud, is merely a bit of ugliness that we learnt to cope with but would have avoided if hindsight were foresight.
Inside the hut we built a semi-circular mezzanine out of old timber which became our bedroom. Of course this is fine when children are either non-existent or young enough to not mind sleeping next to you. An interesting fact: the attractiveness of a larger house with separate bedrooms grows in direct proportion to your offspring. The floor level had a small sofa, a dining table with four chairs, some wine-box bookshelves and a kitchenette with a fridge and work surface. Fine, but...
Ours is a simple one room hut. In number three of the Earthship coffee table books, there is a plan for a hut with a greenhouse out front for the kitchen/bathroom area. If I could rewind and re-record, I would definitely build this addition onto the hut. It would have been a lot more work at the time, but I think it would have been worth it to have an indoor loo and a kitchen we could actually cook in. You see, one of the downsides to hot air rising and having a mezzanine bedroom is that everything you cook inside the single-space hut wafts up into the beds. Think curry pillow cases and fishy blankets. If we ever wanted to do anything other than boil water or make aromatic coffee, we had to scoot outside and cook on the BBQ. Oh yes, it's lovely in nice weather. So is strolling fifteen metres through the garden to your bathroom.
The floor is another thing I would like to mention. I don't know about American slate and slabs of paving stones, but over here, they are incredibly varied in size and thickness. We used lovely big black slate slabs and it looked gorgeous but NOTHING was ever level and it was maddening. In fact, once we tiled the big house, we ripped up the slate in the little house and replaced it with left-over ceramic tiles. So nice. So clean.
Our hut was one of the ones that used a double rebar birdcage for the roof. I don't think they do that anymore, but I might be wrong. This is where we tied our rebar to the Ls that we had planted in the bond beam. It became impossible to stuff insulation between two bars tied to one post (yes, I know...duh) so there is a big strip of non-insulated roof. I think it would have been better to sink a double row of Ls with enough space for the insulation between them. We should also have used a lot more horizontal rebar to avoid the saggy-baggy-elephant look and make a prettier shaped dome. Speaking of rebar - and this was advice from Tom and Amy well worth paying attention to - you have to cover the metal with either paint or cement before plastering over it. The plaster eats at the iron and you can end up with big rust stains all over the place. We only have a tiny one thanks to the Dukes (and our own slightly-less-than-perfect cover-up job).
Still on the roof, we also included small vents into the air chamber between the two domes to allow ventilation and avoid condensation. They should probably have been a bit bigger, but they seem to do the job pretty well.
Repeat after me:
All the same size...all the same size...all the same size...