Terry rescheduled the insulation crew for next week, giving us time for a final push to complete the electrical systems. This week we installed numerous fans (for bathroom venting) and cans (recessed ceiling lights) and a host of other boxes for outlets, switches, sconces (wall lights), and flush-mount overhead lighting (chandeliers and their ilk), as well as telephone, TV, and ethernet connections. If it sounds like a lot to keep track of, that’s because it is.
Wiring the fans takes a little bit of electrical know-how, so Colin took care of them. Meanwhile I laid out, installed, and wired all 51 cans in the house so far. The can layout is a fun challenge. I want to space them equally across the ceiling in both directions so they look nice and light the room evenly, but I need to avoid all the trusses, pipes, and ducts. Oftentimes these obstacles prevent a perfect grid, so the cans wind up slightly offset. I just arrange them as close as possible to the desired grid, and trust that nobody will notice if one row of recessed lights is an inch off in the finished house.
Every set of hard-wired lights gets a switch. Some get two or even three switches… as an extreme example in this house, you can control the basement hallway lights from either the top of the stairs, the bottom of the stairs, or the entrance to the family room. Having multiple switches control the same lights is sort of interesting. Think about it: you flip ANY switch, and it toggles the lights. How does the switch know?
Turns out you have to connect the switches using special cable that has two hot wires instead of one. The switch plates themselves have one or two additional wire stubs where you can connect the extra conductors. The way you wire them together is pretty ingenious – it allows current to flow through one or the other hot wire, and it either completes or breaks the circuit no matter which switch you flip. Colin drew me a diagram (on a wall stud with a carpenter’s pencil, of course) showing me how it works.

Show this diagram to an electrical engineer and ask how a three-way switch works. It’ll make sense real fast.
We completed plenty of other mini-projects this week, too. I’m tired of writing so here’s a photo gallery instead.
End of the day Friday, Colin and Terry triple-checked that we haven’t missed any circuits. Once the insulation goes in, it cuts off our access the exterior walls… and the insulation crew will arrive at 7 Monday morning.
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