Straw bale Walls

First of all, sorry that it has been a couple of weeks since the last entry. We got a bit busy last weekend and during the week it has been work, work and more work. But things have really happened since our last entry, as pictures below will show.

Having finished the eves lining and the colourbond walls it was time to start working with straw bales again. Initially we had planned to start working on the northern side of the house, but due to summer sea breezes we changed our minds and started on the south instead. As such, the first room to be done was the en-suite bedroom and then the music/movie room. The latter also has internal straw bale walls, and we decided to do most of these at the same time in order to get the corners to the external walls done properly.

Step by step, this is what happened.

First step was to put down the plastic membrane over the besser blocks. This time we made the plastic a bit wider to cover the sides of the bales and to fix the plastic on top of the first course of bales.

Three layers of bales completed. First layer covered completely in plastic

Eastern wall of en-suite bedroom

Wooden sub frame which later will hold the window. Bales are butted up against the sub frame and then stitched with baling twine to the sub frame. On top of each layer of bales, barbed wire is tightened between the posts and then pegged down into the bales. The end is nailed to the wooden sub frame.

Closer detail of bale around steel post and butted up against the wooden sub frame

Completed southern wall for the en-suite bedroom

Completed eastern wall for the en-suite bedroom

En-suite bedroom walls seen from the inside

The next stage to be completed was then putting on the chicken wire on the inside and outside of the bale walls. Last time we used a curved needle to stitch the baling twine onto the bales. This time we decided to make metal pegs out of fencing wire (3.15mm thick). The wire was cut using a angle grinder, then bent into a u-shape by inserting one end of the wire into a copper pipe and bending it over.

Having tried both these methods we have found that using the pegs is much quicker, though in some places we are still using some twine to stitch the wire on, just to make sure it sits tightly onto the bales. With the wooden sub frames we use a staple gun and basically just staple the wire onto the wood.

Chicken wire covering bales and plastic around wooden sub frame

External walls covered with chicken wire

Door way covered with chicken wire

Wall ready for rendering - seen from the balcony of the little cabin we are currently living in

The third step was then to put on the first coat of render. Again we have made a small change from what we did with the garage/workshop in that we are now not including bondcrete in the mix. We used bondcrete on the outside of the garage/workshop and tried without on the inside. We found basically no difference in how the render stuck to the bales and as such we have decided to skip it for the main house. This saves money and it also makes the render mixing job a bit easier.

Otherwise the mix is the same as before: 12 parts of course sand, 4 parts of fat sand, 4 parts of lime, 2 parts of cement and then water to make a mix similar to that of a chocolate cake mixture. In terms of making the work efficient we start by making one mix and putting it in the wheel barrow. Then immediately we mix another which is left running in the mixer until we have used the first one. This works very well, but we sometimes have to add just a little bit extra water before using the next batch.

The render is applied by hand and we push it as far into the bales as possible, trying to fill in all holes that might be there. The chicken wire will often be on the outside of this first coat of render, something which is good as it will then help re-enforce the second coat.

The final result after two days of rendering:

Music/movie room wall leading out to the court yard

Eastern en-suite bedroom wall leading out to the court yard

En-suite bedroom southern wall

En-suite bedroom southern wall on the inside

En-suite bedroom southern wall on the inside

Music/movie room southern wall, partly done

So, as can be seen, we have done some work since last time....   The next step now is to continue putting up straw bale walls. We will now do the section running from the entryway on the southern side, to the second toilet on the eastern side. This will be challenging in some parts as this is the highest wall (about 3.6 meters + 40 cm slab thickness), but hopefully we will manage to get the last bales up safely.

When that is completed we will start on the northern wall. Luckily this wall has a lot of windows and as such there is not that much baling work. Finally, we will do the western wall that will have its own challenges due to the veranda roof structure. But more about all that later.

Finally, just got a link the other day from a friend in Norway who works for the Norwegian Broad Casting Corporation (NRK). If you are interested in some very nice clips from Norway, be it skiing from high mountain tops, surfing in Lofoten, or balancing on a rope across a glacier crevasse, then follow this link:   

http://www.youtube.com/profile?user=TorjeTv

The commentary is in Norwegian, so if you do not understand it, just look at the pictures and enjoy.

Any problems, please email webmaster. This page was last updated 24/07/2008