Turning a 2-dimension house plan into a 3-dimensional building -Resources (Education)- E
Solar Home Chronicles 17
Tuesday, 20 November 2007
A blueprint – a simple piece of paper with lines on it – can never convey the sense of what a home feels like, like real walls, windows and roofs. We had to get our house plans specially approved by engineers, as well as by our local Building Inspector, in order to get a building permit, because it has some unusual design characteristics.
Not only does it have no basement, it also has a particular heating system involving air circulated through ducts in the floor. The insulated concrete slab floor has no footings or frost wall, and instead is insulated horizontally away from the building to prevent frost getting below the slab and heaving it. As well, it has a large roof, and so had to be engineered carefully to withstand our potential snow loads – a special concern because we were using rough sawn non-kiln-dried large timbers to support the building.
So, the Building Inspector had special challenges in assessing and approving our project.
These same characteristics also challenged our builders. Don Roscoe, the Architectural Designer with Solar Nova Scotia, based our home design on a type of home that he has built several times. So, the number of windows in relation to square footage of floor space (an important consideration, to make sure that your home collects just the right amount of solar heat, and no more), the details of the air circulation system, and the general principles of design came easily for him. He just had to make the rooms and layout to suit our particular needs.
The house plans that Don gave us, we soon found out, were excellent guides if you had already built this house before. For us, though, they were quite difficult to use. Drawn to scale, there were no actual dimensions on them. Our builders had to take out rulers, and figure out, down to the 16th of an inch (and then calculate!), how long to build the walls, what angles the rafters were and how big to make the windows.
And this is why I know how well our foreman did in math 30 years ago at high school – because math skills became an important commodity in our home building!
The other “interesting” factor in our home building was the Forestry Stewardship Council lumber we were using. We had ordered edge-planed 2-by-4 lumber that was supposed to be 1 3⁄4 x 3 5/8 inches (note that the 2-by-4’s that you get at the lumber store are actually 1 1⁄2 inches by 3 1⁄2 inches). All of our FSC wood arrived completely rough-sawn, and the full 2-by-4 size. This meant that, unless we planed it ourselves, our interior walls would be wider than originally planned, and probably not uniform.
The lack of uniformity of the studs in the walls would make it difficult to create smooth finished walls. And, at the very least, the building process would be much slower than expected, as every piece of wood was carefully used.
We plan to address this with the Forestry Stewardship Council, because we would like to promote the use of their beautiful wood products – but it is very costly if people have to pay more in labour to use them. We see no reason why the FSC wood cannot meet consistent standards like other wood products.
The house gradually took shape. The framed walls intimated where the windows would be. We could say things like “the box of nails is in the bathroom” and people knew what part of the building we were talking about. We could walk through the `rooms’ and discuss which way the door should swing, or where we should put the light switches.
Eventually, we could even get to the second floor by way of stairs, instead of by ladder.
Getting the impressive 14-foot posts standing up, and the 16-foot, 6 x 12 inch beams suspended across the posts, was an amazing feat of strategic manpower and scaffolding. We had many visitors drop by. Everyone was impressed by the quality of the wood, and the resulting strength of the building. It reminded me of an older home we renovated years ago – rough, solid timbers that would last for generations.
We certainly hope so!
Next time: cladding the framework