Wattle and Daub: A Quick, Easy, and Seismic Resistant Natural Building Option
Many people dream about building their own earthen home, whether that be from cob, adobe, rammed earth, or any other number of natural building techniques. The idea of using the earth beneath your feet to craft with your own hand a beautiful, natural structure that will shelter your family for years to come is indeed captivating.
However, a good number of natural, earthen homes have been abandoned during the construction phase because of the large amount of work involved. Earth is heavy, and the process of mixing clay, sand, straw and other aggregate material to eventually lift onto the walls of your future home is definitely not easy.
For people who live in temperate climates, wattle and daub is one natural building technique that requires much less mixing of earthen materials. While building a wattle and daub house will certainly take a good amount of effort, this style of natural construction is typically much less labor intensive than building with cob, adobe, or rammed earth. Below we offer a quick introduction to building with wattle and daub and some of the benefits that come with this technique.
What is Wattle and Daub?
Wattle and daub is a natural construction technique that has been used by rural communities around the world for thousands of years. In fact, archaeological investigations in Central America, especially at the Joya de Cerén site in El Salvador where a rural Mayan community was covered in volcanic ash, have found evidence that wattle and daub constructions have been in use for over 1,500 years at least.
There are two parts to this natural building technique: the wattle and the daub. The wattle is essentially a wood frame structure that has woven pieces of lattice or branches tied to either side of the wood frame wall. It is important to find branches or other pliable material that can be “woven” horizontally around usually larger and more stable vertical posts.
One example would be to use round cedar posts for your timber frame and then use pieces of thin bamboo as lattice to horizontally connect the posts. You will end up with a timber frame structure and hollow walls encased by horizontal lattice.
The daub is an earthen mix, similar to cob, which is made up of 75% sand, 25% clay, and large amounts of straw or other fibrous material. The high sand content in your soil assures that there will be limited amount of cracking once the mix dries. The daub is used to fill in the hollow spaces between the horizontal lattice (or wattle) and to also plaster the wall, covering the individual pieces of woven lattice.
To build a simple wattle and daub structure, you´ll need to first find several posts that will function as the structure for your walls. Bury these posts every two to four feet to give you a square or rectangular structure with similar heights to facilitate attaching a roof.
Next, take several smaller branches or other pliable, wooden material and weave them through the upright post structure. You basically want a mat of branches that you will then use to plaster over with your daub.
If you can´t find lattice material that is sufficiently pliable to weave between your upright posts, you can also nail slabs of wood or more rigid branches to either side of the vertical post structure. This will make it a little more difficult to fill in the “daub” in between the posts, but will also leave you with a slightly thicker, sturdier wall structure.
Once the daub has dried, you can plaster the inside and outside of the walls. Exterior plasters are usually best done with lime to offer more water resistance.
Benefits of Wattle and Daub Construction
The amount of earthen material that you have to mix for a wattle and daub home is significantly less than if you were building a cob or adobe home with 18 to 24 inch thick walls. Wattle and daub construction, then can usually be completed more quickly and efficiently than other earthen building techniques.
While your wattle and daub walls won´t be any thicker than 4 to 6, that doesn´t mean that you will be sacrificing any sort of structural soundness. Rather, wattle and daub structures are known to be extremely anti-seismic. The large amount of vertical and horizontal wooden pieces that are held together by an earthen “glue” can withstand substantial movement without comprising and structural integrity.
Lastly, wattle and daub structures also can be combined with other natural building techniques. For example, if you wanted thicker outside walls to maximize the thermal mass, you could use cob or adobe for your exterior walls and build with wattle and daub for interior walls that take up significantly less space inside your home.
A wattle and daub home will last for decades as long as you keep the walls somewhat protected from the rain. Wattle and daub structures have been built by different cultures around the world for thousands of years. As long as you have a plentiful source of tree branches, twigs, clay soil, and water, you can build a semi-permanent structure that will keep you well protected from pretty much every sort of potential danger in your surroundings.
Feature Image from: https://permaculturenews.org/2013/04/26/bamboo-wattle-and-daub-structures/