Why use Straw Bales to Build?
As we move towards a greener way of life, interest is growing in straw bale houses where bales are used for the construction of the walls instead of traditional brick and block materials. There are many misconceptions about this method of building but almost all of them are completely wrong!
The main worries appear to be about pests, fire risk, energy efficiency and also the installation and fixing of plumbing and electrical work but they all disappear when confronted by the facts.
When you examine the facts, straw bale houses perform better than traditionally built and timber framed houses in nearly all of the areas that people are concerned about!
And from a green point of view, think of the savings involved when millions of tons of straw are burnt world-wide every year sending huge quantities of carbon monoxide into the atmosphere plus the cost in fuel transporting traditional building materials to building sites.
It is estimated that over 400,000 houses a year could be built in the UK using straw bales from farms and British suppliers!
How to Build using Straw Bales
The straw used for building purposes comes from wheat, barley, oats and rye crops.
The walls must be laid on a brick or concrete slab and the first course of bales should be 250 to 400mm above ground level.
They can be laid as bricks in a simple stretcher bond pattern or, more commonly, laid as infill panels in a timber or steel frame. A typical bale size would be 900 x 450 x 300mm thick with a U value of 0.13 which is twice that required by building regulations.
But it is the cost difference that surprises most people! For a typical facing brick and blockwork external wall in a traditional house, the materials should cost between £40 and £50 per square metre, depending upon the quality of the facing brick.
A square metre of straw baling, however, would cost between and £6 and £8 – plus a huge saving in labour costs as well! Most self-builders are extremely budget conscious and savings like these can influence major decisions at the "shall we/shan’t we" stage of a project.
Non-experts can do straw baling although it is better to attend a training course first or look at videos guiding the way through the process. Alternatively there are firms who specialise in this type of work and will either offer support to beginners or take over the whole project if required.
There are also training courses, books and videos available to new straw bale enthusiasts wanting to find out more about this very old technique of building that is now discovering a new lease of life due to the growing awareness of global warming and the rise of the eco warrior!