Wednesday was an exciting day. I knocked a hole through Bob’s dining room wall into a corner of the bathroom upstairs, and then fit a vent through. It’s the first piece of a novel system for heat transfer within the house.

Let me explain the reason for this odd-looking arrangement. Bob has a very cozy pellet stove in the dining room, and he wants to draw that heat into the living room. We’ll accomplish his goal with a duct and a built-in fan. The high placement of the intake vent allows it to capture heat rising toward the dining room ceiling, while the outlet gets built into a floor to warm the living room’s full height. Our duct will take a labyrinthine route through the house: along the upstairs bathroom’s exterior wall, behind the knee-wall running the length of the upstairs, down the chimney race to the basement, then back up to the living room floor.

The proposed duct route.

It took some work to determine where the intake vent should go. First I scraped and sawed all the foam insulation out from that part of the wall. We drilled a pilot hole with a long bit and left it sticking out on both sides for a consistent point to measure from. (Poking random holes in walls: you just can’t do that with new construction!) In the dining room we came out mighty close to the ceiling, while on the bathroom side a couple studs and the wall’s bottom plate further constrained us.

At last I worked out where the 8-inch square hole should go, and I sketched it on both sides of the wall. (Drawing on the walls: another new-construction no-no!) I cut the hole out from the dining room, standing on a ladder. This wall was part of the original farmhouse, and the sheathing is quite thick, so even with a sawzall I had a dickens of a time getting through. It took the better part of an hour. I feel bad for Suze, trying to work at her computer just across the room while I generated so much sawdust and noise.

Rough-cut vent hole from the dining room side.

I paused frequently to check that my hole was coming out in the right place on both sides, and that the nearby electrical cables stayed well out of the way. Since I had no choice but to saw directly through an original stud, I installed a mini-header above the hole to transfer the support. (Thanks to redundancy, the house did NOT come crashing down while the stud stood unsupported.) The edges of my hole started out pretty rough, so it took a bit of trimming and testing and trimming some more before the vent successfully squeezed in. I can’t tell you how many times I made the circuit from the dining room side of the wall up to the bathroom side and back again.

Dining room side.

Bathroom side.