The Food Forest

How to Build a Strawbale Wall

Straw bale walls can be built very much like brick walls, stacking the bales on top of a concrete foundation with a damp proof material (heavy plastic) between the concrete and the bales to stop any moisture getting from the ground into the wall. They are held down firmly by high tensile fencing wire or rods which are attached to a ‘top plate’, something strong like a wooden frame or steel reinforcing sheet which holds the bales firmly onto the foundation. If using wire, it is passed through a curved piece of ‘poly-pipe’ which is set into the foundation. Many Australian designs simply use reinforcing mesh as a top plate and high tensile fencing wire as a tie down.

tying down strawbales

sculpting bales

Bales can be stacked on the flat or on their edges and can be sculpted to fit. A trick we developed to save costs and resources in building garden walls is to use the bales on edge rather than 'on the flat'. The foundation can be narrower and less bales are used. The top plate is 300mm wide trench mesh which is bought in 6m lengths. It can be bent into curves up and down and partly cut and joined into curves from side to side, giving you absolute flexibility in the shape of the wall.

pole frame construction

In some constructions the roof rests on the walls and in others there is a pole-frame supporting the roof. If you want to be sure your walls stay dry it is easiest to build a pole frame and roof first.


An amazing hand-operated tool called a Grippler is used to tighten the fencing wire around the wall, using little gripping devices called Gripples. It is simple for anyone to use and can be purchased from stock&station agents.

chicken wire on bales

Then the walls are covered with chicken wire (netting) which is knitted from one side of the bales to the other with binder twine using big (75cm long) needles. They can be made cheaply by a welder.

mixing the cement

Finally the wall is plastered with a cement render.

Rendering is one of the most satisfying parts of the operation and is remarkably easy. We use a mixture of 6 parts plasterers sand, one part lime and one part cement.

cement render of wall

The cement render sticks to the straw and to the netting which forms a strong ‘ferro-cement’ layer. With two more coats of render, each a bit more than 1cm thick, the total plastered layer ends up being about 3-4cm thick. The first layer should leave the netting partly visible and to save costs we use ordinary grey ‘blended cement’ in the mortar.

trowel and hawk

It is well worth getting a plasterers trowel (which is rectangular and bigger than a brickie’s trowel) and a hawk (a square piece of wood with a handle under it) to carry the mortar from the barrow to the wall. For the faint-hearted you can don a tough pair of rubber gloves and smear or throw the mortar onto the wall. This works well but is slower than using a trowel.

sand mix

The second layer is used to give you pretty much the exact shape you want and for this and the final layer we use a light coloured cement (like Brightonlite), which allows the colour of the sand to come through. Some plasterers sand is yellowish, which leaves you with a very light sandstone colour, as seen in the pictures of our walls; alternatively you may want to go for a dark red or brown sand. You can also use a shovelful of earth from your own property, as long as it is finely screened which can give you a wall which virtually merges into the landscape.

rendered wall

The final layer on garden walls needs to incorporate a waterproofer which can be mixed into the render or sprayed onto the wall after it is finished. We actually put a layer of plastic between the netting and the straw on the top of garden walls as an extra insurance against water entering the wall (see photo to the right).

waterproofing the wall

Where wooden uprights emerge from the wall to carry a trellis, a non-hardening mastic joint should be made so that there is not even the tiniest crack for water to sneak through, the goo is available from hardware shops.

 trench for wall

You’ll have no problems with termites, insects or fire with a properly built strawbale wall but water in the straw is fatal so the wall must always have good drainage around it and the foundation must be proud of the surrounding ground. Having high powered sprinklers which spray the wall for long periods of time is a poor policy!


Footing for a curved wall. Note the starter bars set in the  concrete. Curved poly pipe has also been set in the foundation to allow wire to be passed over the wall and through the foundation for tightening.

waterproofing around windows

Waterproofing around windows and posts is important.


Windows add interest and can be opened or closed depending on circumstances.


You can even build a moongate in your wall by bending trench mesh into a circle or elipse and strawbaling around it. Little windows built into the wall add enormous visual interest allowing for selected views while the wall cuts out unwanted sights and noise. The walls around our studio make you quite unconscious of a thundering great shed only 20m away and eliminate traffic noise from the busy Gawler Bypass.

You can now do a one-weekend course in strawbale building at The Food Forest to learn the tricks strawbale pioneers had to discover over years of building and to meet architects and engineers who are comfortable working with strawbales. Courses are also run in most states and you can find out about them via permaculture associations and networks.

Attending a workshop or helping on a strawbale site is the best way to get a realistic idea of whether you would want to build in this medium. Happy building!