It feels good to be working on the tiny house again (this is Brian) after a 30 day work push to fill a last minute commission for some challenging traditional Inuit kayak frames (my day job, Cape Falcon Kayak, is worth checking out if you like beautiful things made of wood).
After admiring the perfectly flat finished and painted sheet rock walls that Liz just finished, I brought out the holesaw and started drilling for the bathroom fan and passive air vents.
For our active ventilation strategy we are using a Panasonic Whispergreen Select multi speed fan with an integrated light. This energy efficient quiet fan is popular with tiny housers because it can be set to continuously vent at 30cfm in addition to its normal higher setting, which is about triple what you need but it’s the lowest continuous CFM venting fan we’ve found, and it’s cool that it’s integrated. This fan also has a moisture sensing unit which is attractive in a tiny house, but the module gets poor reviews so we are opting for a moisture sensing switch instead. We’re hoping this fan can be our all purpose exhaust fan but we’ve installed another wire just in case we need a dedicated cooking fan in the future.
For make-up air we’re putting in two Panasonic passive air vents. These little 18cfm vents are easy to install, attractive and can be opened and closed. We’re putting one up high on the west wall and one down low on the north wall to encourage cool-to-hot cross ventilation. I’m going to be monitoring the indoor air CO2, humidity, and temperature for the next year to get some real data on tiny house ventilation. It’s always fun to collect numbers as a counterpoint to the anecdote and opinion that seems to dictate so much of tiny house design.
Today I discovered yet another awesome thing about rock wool insulation, you can drill through it with a hole saw!
– Brian
