Last time we worked on the wood frame construction of the straw bale building. Now we had to add 6 beams that will support the roof, and a lot of boards (4 cm / 1.57 in thick).
The distance between the beams is 1.5 m / 5 ft, so I had to choose very thick boards that will not bend under the force exerted by snow on the roof or someone walking there. Too much deflection would cause the roofing felt to tear, and we don’t want that obviously. 😉
At the moment I think I should add extra beams to minimise the deflection, which would allow me to reduce the thickness of the boards. Boards would be cheaper, which would save me some money perhaps. At the beginning I wanted to use OSB boards, but they wouldn’t be able to hold weight of the snow, so I had to use typical wood boards.
Oh, another important things. I ordered the boards 4 cm thick and 3.0 meter (10 ft) long, and a small part cut to 1.5 meter (5 ft) lenght. I didn’t care about the width. But none of the boards fit my specification — all were a couple of cm (an inch or two) to long. I didn’t have any good wood saw, so the boards were nailed to the beams overlapping. This will be corrected in the future.