If there is one lesson I’m learning as I explore straw bale construction, it’s that there is no one way to work with straw bale. This form of construction involves a lot of craft, and experience is very valuable, but it is a form that is being re-invented all over the country, and each builder develops their own approach and style.
Each straw bale structure is truly a custom building, responding to the requirements of the site and the owner and the materials, and the workers. Each project requires a certain inventiveness to bring it into being.
Shaping and stacking the bales created a solid, but slightly wobbly wall. (See my post Straw Bale Bending Walls) But what made that wall really snap to was stitching the bales between walls of chicken wire.
“Most people don’t want to stitch,” said Mark Morgan of Bearpaw Design and Construction, our workshop leader. He learned how to stitch straw bale from a friend who weaves.
The process resembles the basic stitch created by a sewing machine, with a giant, threaded baling needle pushing through the bale like a sewing needle pokes through fabric. And on the opposite side, another sewer threads the bobbin through the loop. The needle pulls back, the needle twine and bobbin loop and pulled tight with the loop pulled into the middle of the bale, drawing the stitch firm.
This process makes me feel like one of the little mice sewing Cinderella’s ball gown. Perhaps that feeling was especially strong because of the round room we are working on.
So start by covering the bale wall inside and out with chicken wire, which is nailed to the wooden framework with roofing nails. The wire should extend an inch or two below the bales and over the Styrofoam below. You can also pin the bales together with pole barn nails or even sticks of willow or whatever wood you are cutting back in your area.
Loop poly twine through the notch in the needle and push it through as level as possible. If the needle does not come out where the person on the inside thinks it should be, they can give the needle pusher guidance to try again until it comes through properly. The bottom row should be pushed through just above the Styrofoam.
When the needle comes through, the bobbin worker removes the loop, and the needle is pulled back. The bobbin worker makes sure the loop is not twisted, and then threads the bobbin through. Thread it from the bottom of the loop up through the top loop and from the top down through the bottom loop.
When the bobbin is threaded, the bobbin worker calls the needle threader, and they both pull their twines taught while pounding that area of the bale with their free hands. The loop will be pulled into the middle of the bale. (Any knots in the twine should also be pulled inside the bales.)
Keep stitching along the bales horizontally in a zigzag with stitches about 10-12 inches long.
Communication between the two bale stitchers is key.
Categories: Eco architecture