Benefits:
- Thermal mass
- Widely available building material
- Structurally sound and fire-resistant
- Beautiful
- Ideal for passive cooling
- Fun and easy
Making bricks:
- Prepare frame for drying bricks. Any wood will do. If making bricks alone use this frame as you can pick it up yourself:
If two or more people making bricks you can make a longer “ladder-style” design to make more at one time:
- Dig up a pit of subsoil you want to use. Fill pit with water and flood mud with water. You will need to let the mud soak depending on the stickiness of your clay. It will cause you more work if it is not soaked long enough.
Barefoot (or with long waterproof boots if you have sharp rocks in the mix) get into the pit. The mud should loosen and break up as you walk on it. If it feels like you are compacting it more, it hasn’t soaked long enough or you have too much clay content.
- Stomp and dance in the pit until the mud becomes uniform. It should have enough water that it is easy to mix but is not as runny as slip.
- Add rice husks or short straw to the mix. Add until uniform and there is enough that when you pick up a handful, maybe half is fiber. The liquidity should be such that if you stomp and bring your foot back up it should just hold the print before collapsing into itself.
- Lay frame on dry, relatively flat surface. Dirt is best as laid on concrete or plastic will increase drying time. Put mixture in buckets and bring to frame. (Ideally your brick-making drying area and your housing site will be close to one another as moving heavy bricks is tiring.) Pour mixture into frame filling all holes and swiping the top level with your hand or a piece of wood. Do Not Make it Beautiful!! The biggest problems people make that slows them from making bricks quickly is worrying about the aesthetics of the top of the brick. No one will see this part anyway and a general level is good enough!
- If you’re doing the ladder-style frame get a partner and lift from both sides at the same time. Mix should hold form as brick but slip out easily of form. If the mixture sticks to the frame, it’s probably too dry. Add more water to mix and try it again. If it’s not holding form and the bricks are slumping when you bring form up, they’re a bit too wet and you need to add more fiber or mud.
- Move the frame and lay it down next to the last bricks you made and repeat.
- Leave to dry for a day and check them again. If they hold form you can flip them up on their skinny side. This will speed drying process.
- Allow 7-10 days of good sunny windy days to dry.
Building:
To build you will need bricks and mortar mix.
To make mortar, mix just as you would for bricks except you can make it a bit thinner.
Lay the first layer of bricks on the top of the foundation if
you are using one of straight on the ground if you are not with a layer of mortar under them. When laying mortar, it works well if you smear it on the underlayer in a slight mound running down the center of the bricks. When you lay the next layer of bricks on top of this it will spread out evenly making a suction in the center and spreading to the sides of the bricks without creating more mortar falling off the side when compressed with top brick. You then add a bit of mortar to the butt of the brick you will be butting up against to lock them in sideways.
The most important thing to remember in laying bricks is that they overlap and interlock. You want them to look like this:
And not like this:
Since your bricks will probably not be perfect and the shape of your building may be organic, you will come across places where your bricks start to line up accidentally. Just keep continual watch over it and you can place a half-brick in where you need it to recover the interlocking pattern.
A fast way to build is to build in teams, one person laying the mortar and the other laying the bricks continually over it.
The other important aspect to watch is the lean of the walls in trying to keep them straight. Once the walls get too high for us to be over them building, we choose a side and whatever side we are building from we tend to lean the wall away from us. It is hard to see from that angle. The way to look out for this is to have someone sitting and building from on top of the way looking down on it or to periodically have someone getting on top of the walls and walking them looking down to see where they lean. At this point you can still easily adjust the lean by hitting these bulges in with another brick.
Once you get up to the height you wish for the tops of the walls you can level them using cob and cob in the roof beams onto the top of the adobe walls. Then you can nail the rafters onto the wooden beams.
If you don’t wish to use wood and other materials for the roof and live in a dry climate, you can make an earthen roof by bringing in the bricks one layer at a time slowly closing it off at the top. You can also make a flat earthen roof by laying beams across on the top of the adobe walls and filling in with a straw/clay mix over top.