With the floor built and the timber frame sitting comfortably on top, it was time to build the house’s outer skeleton. The perimeter consists of two stud walls sandwiching a void for insulation, 12 inches thick in all. On the original structure, the timber frame carries the weight of the gable roof, leaving the double wall to support only its own weight and the effect of wind. On the addition, the double wall also supports a shed roof.
We use rough-cut lumber for the stud walls. Our 2×3 studs (ACTUAL dimensions 2×3) are actually larger and stronger than dimensional-lumber 2x4s (actual dimensions 1½x3½). Cillian prefers rough-cut because it gets processed less than planed dimensional lumber, for a lower embodied energy. I’m learning a ton from this architect about environmental conscience.
A disadvantage of rough-cut lumber is that it’s hard to make pencil marks on it. Rowan, Ben, and I did our best to follow Cillian’s very explicit drawings which detail the location and length of every stud. The boards also tend to be warped, so I crowned each piece before cutting it to make sure I oriented the bend toward the insulation void.
We also built pump jacks – homemade scaffolding. The basis of the pump jack is a steel bracket with a ratchet on one side. We fit three such brackets around a trio of 4×4 wood posts, raised the posts vertical, and anchored them to the timber frame. The ratchets enable the brackets to climb or descend the posts. By pumping the brackets to roof height and laying long 2x12s across, we made ourselves a temporary work platform.
Anticipating heavy rain one night, we made a big push that afternoon to install rafters for the shed addition so we could cover it with a temporary roof. Rowan and Cillian stood on the pump jack platform, and Pat and I fed them one open web joist at a time. Cillian aligned the pre-cut joists with the gable slope on 2-foot centers so Rowan could nail them down. Meanwhile, Ben manned the northeast wall and nailed down that end.
Night fell, and we turned on some work lights. Fighting numb fingers, we unrolled a massive tarp over the gable roof, overlapping an equally massive sheet of poly we used for the shed roof. Additional poly enclosed the walls. Wherever possible we avoided screwing directly through the plastic materials, which would create a puncture and (in the case of the tarp) a starting point for rips. Instead, we sandwiched the edges of the material between two pieces of lumber and screwed THAT to our building. Lots of jokes thrown around about Clayton preparing to live in a tent.