After finishing the roof and window rough openings on the strawbale shed in early January, I started building the bale walls. It is a long, laborious, time-intensive process starting with stacking the bales in the wall, stuffing cracks, running electrical, plumbing, and meshing the walls, all prior to plastering.
Fortunately, “baling” doesn’t take any special skills to do well. Looking back now that most of the work is completed, I understand well why people try to have a large group of helpers when they build strawbale homes! If I ever build another structure with this technique, I’ll definitely see if I can host a party.
To start, I would pick a bale from the pile, trim it to size with an 18″ chain saw, re-bale it if necessary, and then stack it on the wall. (A chain saw is one of the best tools for cutting and shaping bales.) Ideally, the bales should fit tightly together, with the later bales being pounded into place. A floor tamper and plywood shims worked really well for this purpose.
Because of the way the shed was designed and how small it was, about half of the bales needed to be re-baled. There is a special knot that you use for re-tying bales. Some people call it a Miller’s Knot, but I’m not sure that is the correct name. It’s an interesting knot, though, in that you can pull the twine taunt and it holds tightly from friction alone. (A half hitch is added for extra precaution.) Re-baling was time consuming but by the end I got pretty good at it.
After the wall was nearly complete, I took a break from the bale stacking to finish the back of the retaining wall. My Dad was able to help which made the process go a lot faster. We placed a perforated french drain around the bottom perimeter, sloping it to drain around the east side. After placing the gravel, we realized that waterproofing the back face of the wall was a good idea, so we pulled the gravel away from the very bottom before applying the several coats of asphaltic emulsion. (We didn’t waterproof the blocks opposite the utility area since it’s not a huge issue if it leaks there…besides this is San Diego and it rarely rains here!) It didn’t take a long time to remedy the oversight, but it pays to do things in the right order.
We plumbed in water from the stubs that I had placed in anticipation of one day building the shed while running a water line past the area in early 2019. Electrical power was tapped off of the well pump solar panels about 120′ away and brought in using #8 wire. The panels will supply about 650 W in full sun, which will be plenty of power to keep a small battery bank fully charged.
I placed another 8″ of soil on top of the plumbing and electrical feed-thru’s, marking tape, and then finished the back fill. Finally, we shaped a gentle brow ditch along the back. I’m planning to plant the slope with ice plant or similar ground cover once the wet season returns.
French drain along the bottom of the retaining wall. 
Drainage gravel 
Back filling after completing the plumbing. Dad applied several coats of asphaltic emulsion to the block wall for waterproofing. 
The well pump solar panels supply electricity. 
Running the electrical line 
1″ electrical conduit passes thru the wall to the utility area. 
Marking tape is always helpful. 
Finished backfill!
I also spent some additional time finishing up the roof before returning to the walls. I installed R-30 unfaced insulation batts in 2×6 cavities furred down with 2×2’s to give enough depth for the insulation to fit. Dad helped run the wiring for the ceiling light cans and the install the building paper vapor barrier.
To hold the can fixtures in the ceiling, we cut a hole – just large enough for a can to slide thru – in a 3/8″ plywood plate. To secure the can on the plate so that the rim was flush with the final plaster coat, I installed three 3/16″ dia aluminum rivets thru the sides of the can about 3/4″ from the rim. The can slides up into the plate until it hits the rivets and is held in place by the three springs that come with the can. It wasn’t perfect but it worked fairly well.
The last part was to install the rib lath horizontally across the rafters. We stapled the lath onto the rafters with 1″ staples. I had an after-thought that maybe the staples weren’t strong enough the hold 3/4″ of plaster over 80 sq ft but it seemed fairly strong. We’ll see how well it holds up! Hopefully it won’t be an issue. Once the rib-lath was installed, openings for the cans were cut away and the lath carefully stapled thru into the the plywood light plates behind to lock them into place.
Insulation on the east roof. 
A crisscross of tie-wire holds the insulation in place. 
We forgot to dill holes for the electrical wires beforehand so had to do it after the insulation was in place. It worked. 
A can lighting fixture holder from 3/8″ plywood. 
3/16″ rivets on the near side set the thickness for the roof plaster to ~ 3/4″. 
Because the can lighting will be low voltage (24v) and difficult to access, all the electrical connections are soldered prior to the wire nuts. 
Can lighting fixture installed. 
Building paper installed. 
I used a single layer of paper between the plaster and the insulation. 
3/8″ furred metal lath (high rib lath) run horizontally across the rafters (later picture) 
Ready for plaster (later picture)
For the round window in front, I installed a floating window frame out of spare 2×6 pieces. Once the frame was installed, I cut the remainder of the bales out with the chain saw using the frame as a rough guide. The inside of wall around the window is shaped with a gentle curve. This allows light passing thru the window to still spread on the inside, in spit of the thick walls.
The pockets were cut on the ground and then the bales hoisted into position. 
Window frame installed. 
The second bale installed. 
Looking south thru the window. This image was taken much later on in the process prior to shaping the inside. Spray paint marks the outer edge of the shaping (~ 8″).
For electrical, I ran all of the wiring inside of ENT conduit thru the walls. Because the lighting is low voltage DC and the outlets are mostly AC, I ended up with quite a few more wires overall; though it was probably still an overkill. I drilled holes in re-work boxes with a hole saw and then installed an ENT conduit fitting rather than using ENT specific boxes. The re-work boxes work well because the back tabs hold onto the plywood mounting plate nicely and they are cheaper than the ENT boxes.
Electrical wiring before working the conduit into the walls. This is at the electrical feed / “subpanel” area. 
The wiring exits outside of the wall in 1.5″ black pipe. The white pipes will bring in power from the adjacent utility area. 
All the wires are marked with a sharpie during installation so we don’t forget where they go. 
I used re-work type outlet boxes so that they would hold well to the 3/8″ plywood mounting panel. A 3/4″ outlet extender sets the depth of the box beneath the plaster.
After a lot of hard work over three months, the straw house is finally beginning to take shape. Mom helped cover most of the exposed wood with tar paper which was a big help. (She said she enjoyed it as well!) Then came installing the mesh. Correct mesh installation is important because the mesh, along with the plaster, is what gives the shear strength to the building. I used 15 ga 2×2 mesh in a 5′-wide roll. Starting at the top, the mesh is stapled into the top 4×4 with a double row of 2″ staples spaced every 2″ (alright, probably another overkill). The mesh is then rolled down to the bottom where the “hippo forks” are used to stretch it taunt while it is being stapled similarly to the bottom.
Once the mesh is installed on both sides of the bale, the mesh is sewn together thru the bales with baling twine. A “needle” is used to pull it thru the bale wall. The stitching helps hold the wall together and prevents the mesh from sagging away from the wall when the plaster is installed.
Probably the largest single issue on this build was that the straw bales I used were short of 15.5″ wide. A few measured in at that width, but the majority of them were far narrower – somewhere in the 14-14.5″ width range. I had measured one of the bales earlier but apparently I ended up measuring a 15.5″ bale and didn’t realize that this was mostly an exception to the bales that I had until the framing was completed. The end result is that the framing (top and bottom plates) were spaced for 15.5″ bales, which meant that either our walls would have unsightly variations in them or we could try to even the variations out with stuffing. Our solution was to stuff much of the inside walls with 1/2″-1.5″ of straw between the bales and the mesh. I almost left the variations in the walls, but ultimately decided against it; a decision which unfortunately took a lot of time. Looking back, perhaps it wasn’t the wisest use of time but it worked out! For sure, I’m going to be careful not to make that bale-size mistake again. 🙂
