After the 2010 Faire season concluded, they kicked everyone out for awhile for cleanup, etc. It was a mixed blessing. The weather was very nice and would have been great for working, but on the other hand, we all needed a break after many weeks of spending weekends at the Faire following many more weeks building. We had to pass up a few chances at free rocks, etc. because we had no place to put it. Once the grounds opened up again, we started back in. We took down the plywood and started hauling in rocks and fill again. Silas got right back onto shoveling, raking, and rolling dirt. We obtained a couple of loads of packing sand from Fenske's, a local dirt supplier near Elgin. He suggested the red sand as being very "packable", which we needed for the packed earth floors.
Here you can see the new dirt being shoveled onto the floor. The plywood has also been removed and returned to the theater!
Lots and lots of red sand. It actually did pack really well!
More of the new pack sand was added to the porch and ramp as well as re-doing the rock edging.
Here the floor is filled and ready for final finishing, but that must wait till the walls are done! We're going to be kicking it around for awhile till that is done. At least the extra traffic will pack it down further. Kudos to Silas for spearheading this part of the job especially. He and Michael did the bulk of the floor work you see. The corner you see on the upper left has been filled with dirt and rock over three feet deep to level it out!
At this point I went for a couple of changes. Originally intending wattle and daub walls, I had the idea of going to light straw and clay. I had learned the method in my class for Permaculture Design recently and it seemed a bit less labor intensive, while giving the same visible result.
The following explanation comes from http://www.strawbalecentral.com/techniques3.html
Light Straw-Clay (Leichtlehm)
Leichtlehm (literally "light-loam") is a German technique of ramming loose straw coated with a clay slip into forms as an infill for timber frame structures. This technique has been popularly reintroduced to North America by Robert Laporte who teaches natural building courses nationwide. He has been joined recently by Frank Andresen, a builder with extensive natural building experience in his native Germany.
The technique consists of surrounding a frame structure with a thick infill of the straw-clay mixture. The frame is usually fully expressed on the interior of the building to take advantage of the beauty of the timber frame joinery. A lighter frame of wood is built on the eventual outside face of the building as an anchoring system for the straw-clay walls.
Loose straw and a clay slurry are tossed with pitchforks or mixed mechanically, then allowed to age for up to several days in order to allow the straw to absorb the extra moisture and thus create a stickier and more easily tamped mixture. For higher insulation values less clay can be used. Slip forms are set up between the framing members, and the straw clay mixture is tamped by hand in two-foot layers.
Occasional horizontal members spanning between the exterior frame are placed in order to "lock in" the straw-clay mass. Frank Andresen places the ends of these horizontal members at the upper ends of vertical slots in the frame in order to allow for shrinkage of the straw-clay as it dries. Once each layer is complete, the slip form is moved up and the next layer is tamped until the wall is complete. The walls are allowed to dry before final plastering occurs. Any shrinkage is taken up by stuffing more of the mixture into the cracks.
Leichtlehm (literally "light-loam") is a German technique of ramming loose straw coated with a clay slip into forms as an infill for timber frame structures. This technique has been popularly reintroduced to North America by Robert Laporte who teaches natural building courses nationwide. He has been joined recently by Frank Andresen, a builder with extensive natural building experience in his native Germany.
The technique consists of surrounding a frame structure with a thick infill of the straw-clay mixture. The frame is usually fully expressed on the interior of the building to take advantage of the beauty of the timber frame joinery. A lighter frame of wood is built on the eventual outside face of the building as an anchoring system for the straw-clay walls.
Loose straw and a clay slurry are tossed with pitchforks or mixed mechanically, then allowed to age for up to several days in order to allow the straw to absorb the extra moisture and thus create a stickier and more easily tamped mixture. For higher insulation values less clay can be used. Slip forms are set up between the framing members, and the straw clay mixture is tamped by hand in two-foot layers.
Occasional horizontal members spanning between the exterior frame are placed in order to "lock in" the straw-clay mass. Frank Andresen places the ends of these horizontal members at the upper ends of vertical slots in the frame in order to allow for shrinkage of the straw-clay as it dries. Once each layer is complete, the slip form is moved up and the next layer is tamped until the wall is complete. The walls are allowed to dry before final plastering occurs. Any shrinkage is taken up by stuffing more of the mixture into the cracks.
--- end of quote
The material requirements were about the same, but wattle and daub requires both the vertical members I'd already started installing and woven horizontal members to form a mat that the straw-clay mixture would be plastered onto. Light clay and straw is not so old a method, but it was adapted from wattle and daub and looks about the same in the end.
I made a few of my own adaptations to the style. I retained the verticals to act as reinforcing inside the walls. This was something I hadn't seen done before, but it made sense. I did stop using the saplings, as I found several sources of local bamboo, which is certainly a sustainable material, and tends to be much straighter!
Luckily, we found a local source for the straw. Acceptable straw for use in alternative construction is often hard to find locally. We happened to find someone who had built their own straw bale house and had over thirty bales of good straw left over in storage. We quickly purchased it from him. It is very close to the right amount required for the project.
Once again, Fenske's came through for us. Here is a load of clay we got from them (separated from some of the red sand by a tarp).
We shoveled the clay into the buckets shown and soaked it. We added four more of the half barrels and a lot more of the smaller buckets. We've found it helps to soak the clay overnight. Already soaked clay is added from the smaller buckets as the mix in the barrels used up. At end of day, we shovel in more clay and let it soak for the next day. At start of day, we stir the clay and water, adding whatever is needed of each until the consistency is that of heavy paint or a good milkshake before adding straw. As much loose straw is stirred into the barrel until no more will fit and be covered by clay.
As mentioned in the quote up above, some builders soak the straw in the clay for a day or more. I found that others don't think that makes a difference. We found that soaking for forty-five minutes or so is enough. When the straw begins to become soft and a handful of straw retains the mud on it then it is ready.
Here is a shot showing a row of mud already set and drying, another form filled on top of it, and vertical bamboo pieces ready to go. We went with twelve inch forms, as anything deeper was hard to pack mud into well using hands. You can see a lot of the straw in the mud here, as well as our stockpile of straw bales under the roof. The poles are getting the bark peeled off before they get mud also.
Here's one of the front walls under a window. A bit closer showing a couple of runs of straw and clay, as well as some of the short forms. You can see the difference between the previous saplings and the newer bamboo.
Another shot of the front walls and ongoing forming.
Here is a shot of another new development on the front wall. The framing just visible that somewhat resembles a rainbow will be filled with stained glass ultimately.
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