“Wattle and Cob”:

“Wattle-and-cob” is a technique and term coined by folks at Pun Pun experimenting with adaptations to the traditional wattle-and-daub technique. Wattle-and-daub uses a clay-rich mud mix (daub) plastered onto a woven wall (wattle), usually made from small sticks, woven reeds or bamboo. This technique was traditionally used in rice barns and rice mills in Thailand. In other parts of the world homes are traditionally made from this technique.

Wattle-and-cob uses a similar idea yet instead of having a woven sheet as a wall to plaster on we make a spread out woven frame with small sticks or bamboo. To fill in this wall and make a stronger structural wall we make small strips of wet cob and lay and form those around and in the weave.

Benefits:

• Fast as you don’t have to wait for sections of the cob wall to dry before building up farther since the weave is holding the mud until is dries.
• Easy to do with limited labor resources
• Good for wet climates where drying bricks is not feasible
• Good for raised buildings (on stilts) since the weight of the walls is not as thick as adobe or cob
• Can make walls as thin or thick as you want

To Build:

This technique will not be a load-bearing structure so you can make basic post and beam structure to support your roof. In between the beams connect pieces of branches of wood or bamboo. Connect these horizontally and vertically creating a weave with approximately 6 inch x 6 inch holes in between.

Make a mud mix by digging up subsoil or buying subsoil depending on your site considerations appropriate for building (see above for selecting mud). Soak broken up mud with water covering mud. Mix mud with feet until becomes a smooth consistency and most clumps are out. If it is difficult to get out clumps you may need to soak your mud longer. Add enough water to make it thicker than a slip mix but runny enough to work with easily. Mix will be similar to adobe mix but without the rice husk.

Take long pieces of straw and cover then with the mud mixture. It is important that every piece of straw is thoroughly covered in mud. You can either do this with your hands rubbing the straw back and forth and wiping it with mud or by putting them in the mud pit and dancing on them. When you pull them out of the pit swipe them to remove access mud so they are covered and wet but not extra heavy.

Wrap these strips around the frame you already have in place. You can wrap around pillars and over and down horizontal pieces until they meet the piece below it. It is best to work down to up. At this point is where you decide the thickness you prefer for the walls.

You can build up as much as you wish in one day. Even if it seems unstable, once the mud dries the earthen structure will be what gives strength to the wall, not the frame you made originally.

Plaster and paint as you would any earthen wall.