We started in October and the goal was to have lock-up by Christmas. We designed as we built, the project grew and cost more than we initially planned and used more cement & wood than I originally hoped. The walls are enclosed and the roof is complete. The wood stove will be working overtime as we have no insulation other than the strawbale walls. Although we should be able to camp in the basement close to the wood stove.
I was hoping to do a lot of the work myself but the reality is it's a 5.5 hour drive from our rented home in suburbia and a full time job. I could only put in 1.5 days work each weekend. So I had a contractor do most of the work and hired a friend who has helped build 9 other strawbale homes. Then one weekend I gathered and chauffeured some friends up to help cut and pin strawbales. It was a lot of fun, but it was tiring moving all those bales up to the top for the 10 foot walls. I'm now at the stage where I will complete most of the cabin by myself, partly by necessity as we ran out of funds.
The cabin has a small 24' * 26' outside footprint but seems quite tall as it has a full 8' basement 10' main floor height and steep gabled metal roof with a 8' loft inside the West gabled end.
We initially were going to build a 4' crawl space but my wife vetoed that idea. So we built a 4' pony wall 2*6 construction for a full 8' basement so it could be more usable. Approx. 3.5' of the basement is underground. We have a standard 4'cement wall underground insulated on the outside with 1.5" of recycled Styrofoam sm. The idea is to have the mass on the inside so it can help regulate the temperature, but I didn't insulate the foundation so possibly it could be a direct thermal conduit to ground temperature. I'm a little unsure about what to do right now in this area but I have bigger priorities at this time.
We've used the engineered I beam floor joists and 5/8" plywood for the main floor. The walls to the East, North and most of the West side are post & beam with strawbale in-fill. We decided to use standard 2*6 construction for the South wall and a bit of the West wall due to the size and placement of windows on the South side. We also didn't want to have a deep window sill on the kitchen window, otherwise my wife would not be able to open the kitchen window if it was located 3 ½ feet from the edge of the kitchen counter. Also the stick wall is easier to mount cabinets. We also used stick construction for the gabled ends on the East & West side.
Since we wanted to allow the light to enter the house and not be obscured by the eves we built 10' walls on the main floor. Gabled roof with a loft, so part of the ceiling is cathedral using scissor trusses and part has a 10' * 15' room 8' high in center sloping to approx. 4' on the wall. We put two 16" * 6' flat glass skylights for the southern view in the loft. The roof is a green metal roof which is very long lasting, good for snow country and we can eventually harvest water from it.
The house will be heated by a wood stove in the basement. There is some concern that our stove may be a little too big for our cabin since it will be very well insulated. The strawbale walls will have approx. R40 insulation if we go ahead with the paper cellulose insulation, we had a very expensive quote so we are going to do the insulation job ourselves. we will have approx. R40 - R50 for the ceiling and R20 for the walls. All windows are double pane and we put the largest on the South side and the smallest and fewest on the North side where there is the greatest heat loss. I am still unsure what I want to do about vapor barriers. There's so much controversy on what to do about vapor barriers. Perhaps an acrylic latex paint on the inside of all the walls to make a weak vapor barrier as a compromise solution. It does get cold in the winter and it does get quite warm in the summer. The literature for cellulose insulation states that vapor barrier is not necessary as compared to the way it is required for fiberglass.
The interior and exterior will be utilizing natural adobe plasters. I might add some cement to the exterior plaster near ground level due to splash back. I decided not to screen the bales but I will tar paper and screen all exposed wood for plastering. On the interior We will have approx. 16"deep window sills that will be gently curved for better dispersion of ambient light into the rooms from the windows.
Strawbale details
We purchased 160 bales of barley straw 18" depth 14" high and 38" - 40" in length. We built a 18" plate for the bales to sit on using two stacked 2*4's on the outside and inside for an outside spacing of 18" (the thickness of the bale walls). Then filled them with pea gravel and covered them with tar paper. We then inserted some re-bar into the floor to impale the 1st row of the straw. Subsequent rows of straw is linked together and pined to the box beam columns by bamboo spikes. The box beams are 2*4's spaced 1 foot apart and tied together using plywood and glue. This results in a very strong hollow beam that holds up the weight of the roof and we can also impale the bales with bambo spikes through the box beams. We got this idea from the Strawbale House book, it works great.
We used 24' of 1" zero clearance 6" chimney pipe for the wood stove. The wood stove is located in the basement so it can heat the whole house. We don't have any running water to the house yet. It will be a project in the spring. I am thinking of getting a small pump into the well possibly (solar powered) to pump up to a insulated cistern built into the hill. Then use gravity to pressurize the water flow to the house. I have to do a lot of digging as the ground freezes down to 3.5'.
One of the ideas is to get the bendable copper pipe and wrap it around the stove pipe just above the wood stove to heat the water. I will have to find a suitable tank to store the heated water and a system of check valves and pressure relief valves so that the water can be re-heated if not used.
The floor in the basement is just earth. I was thinking about putting in an earthen floor down in the basement. Possibly with some hydronic pipes for radiant floor heating. I wonder if I can do it with the wood stove and no pump.
One of the goals of this house is that it can be operated completely without grid power. I was thinking about a propane fridge & stove. We have lots of oil lamps and candles and the house faces South with placement of windows for lighting and view. All rooms are designed (except the bathroom) to have natural light from 2 or more directions as recommended in "A pattern language". Yet we have minimized the window sizes on the North & West walls 3' * 2' . We do have a 4' * 4' window on the East side for morning light.
There is still lots to do as we need to build stairs, partition some rooms plaster the exterior walls inside and out. Wiring the house for grid & alternate power. Talking about grid power wow its expensive to hook-up. We paid $1500 for 1 pole 110' onto our property for temporary service. Now they want $2000 above ground and cut down a whole bunch of trees or $3000 underground to span approx. 200' for 200 amp service. They want me to put 200 amp service as I will be building the next house further up the hill. The minimum service allowed by code is 100 amps in that area. My property is in a no zoned area so I do not have to build the house to code, although it is so far. But water & hydro codes do need to be inspected. I built a grey water drain pit to avoid the use of a septic and I am in the process of building the box for a 5 gallon pail composting toilet. I also want to build in a solar oven assessable through the South wall in the kitchen based on the design found on the following Link
Well there it is. All creative suggestions & ideas welcome.
Click here to see some early pictures of our strawbale cabin
Click here to see updated pictures of our strawbale cabin
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