Thursday, 29 August 2024

Twisting wood into a house


These days, you spend your life paying off a house, and even building a shed or animal shelter can be expensive, as timber, brick or any other modern building material requires a heavy investment of money, time and skilled labour. For thousands of years, though, people used a simpler technique that used nothing but natural, local materials.

“Wattle and daub,” as it’s called, takes its name from its two components; a “wattle” was a wicker fence or wall made of a pliable wood like willow or hazel, woven around upright posts like a horizontal basket. Farmers sometimes surrounded their fields with wattle fences, which could be made in modular, lightweight pieces a metre or two high and a metre or two across – hurdles -- and then uprooted, carried to a new location, and stamped into the ground where needed.

The farmer usually created a wattle by putting the upright posts (sometimes called zales or sails on these islands) into a wooden frame (sometimes called a gallows) to hold them in place. Then withies – slim cuttings of willow or hazel – were wound back and forth around the uprights. At the end of the hurdle the withy would be twisted for greater flexibility, wound around the last zale, and woven back in the other direction. Usually a gap would be left in the middle of the hurdle, called a twilly hole, which allowed a shepherd or farmer to carry a few hurdles as a time on his back.

According to author Una McGovern, hurdle fences were vital to medieval agriculture; by keeping sheep confined without the need for permanent infrastructure, they allowed tenant farmers to graze sheep on a patch of land, letting them manure the fields one by one and deposit the fertilisers necessary for cereal crops.

The same technique could form the walls of a building, once a log or timber frame was built and the wattle filled in with a “daub” plaster for insulation and privacy. The daub often contained clay, human or animal hair and cow dung, and hardened around the wattle like concrete around rebar. The technique proved popular throughout the ancient world, among Sumerians, Chinese and Mayans alike. If kept dry the walls would last for centuries, and even now restoring or demolishing old buildings in Europe sometimes reveals wattle inside the walls.

Not all ancient builders loved it; the Roman architect Vetruvius, in the first century BC, moaned about its hazards in his Ten Books on Architecture:

“As for ‘wattle and daub’ I could wish that it had never been invented,” Vetruvius wrote testily. “…But since some are obliged to use it either to save time or money, or for partitions on an unsupported span, the proper method of construction is as follows. Give it a high foundation so that it may nowhere come in contact with the broken stone-work composing the floor; for if it is sunk in this, it rots in course of time, then settles and sags forward, and so breaks through the surface of the stucco covering.”

Vetruvius’ disdain notwithstanding, however, clearly many of his contemporaries loved it, and it’s easy to see why; it allowed people to build a structure cheaply and easily. The main disadvantage, as the Roman mentioned, is that it cannot get damp; like cob, straw bales or other natural building methods, it works best when you build the foundation and walls of rock for the first metre or so.

The technique is similar to building in cob, that mixture of sand, straw and clay, mixed with water and squeezed together – usually by humans walking on it.  Handfuls of the mixture – the word “cob” comes from an Old English word for “lump” – are stacked them on top of each other in a row, stomped solid by people’s feet, and then another layer of cob added, until people have a wall.

The straw binds the clay and sand together; instead of a wall’s mass hanging on a few large structures like girders or beams, it hangs on the many tiny structures of the straw. Once the cob dries it can be almost as durable as stone. Daub needs to be thinner than cob, like stucco or plaster – to be spread across the wattle rather than creating a self-supporting wall – but is can be made from quite similar materials. 

Of course, wattle and daub is probably not suitable for modern homeowners unaccustomed to mud walls. That doesn’t mean, however, that it has no relevance to today’s homesteader; animals don’t tend to mind such all-natural surroundings, as long as the interior remains warm and dry, and neither do garden tools.

Building techniques like cob or wattle-and-daub fell out of favour in the modern era because they are more labour-intensive than our modern building techniques that rely on fossil fuels. We should not let such skills disappear entirely, however, for these methods still have advantages. They are completely ecological, requiring no machines, and generating no pollution. They can last for centuries, as evidenced by homes built this way in Europe – and might still stand when our reinforced concrete has collapsed to ruin. And when a wattle-and-daub home is finally torn down, it merely adds fertiliser to the soil, rather than toxic waste – and another one can be built, literally dirt cheap.

 

References:

Una McGovern, Lost Crafts, published by Chambers, 2009. 

Vetruvius, Ten Books on Architecture, Chapter 8, Section 20. 

Top Photo: Cottage in Heimbach, Germany. 

Bottom photo: Listed building in the UK with original wattle showing. 

Both photos courtesy of Wikicommons. 

 

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