Is an HRV/ERV absolutely necessary?
Hello GBA readers
I have recently finished some energy upgrades to my 1983 house in climate zone 6 (southern ontario). Work included exterior rigid and attic insulation, air sealing, new triple pane windows and patio doors and the installation of a couple fujitsu ductless heat pumps. My energy advisor recently completed a follow up blower door test and results came in at 1.9 ACH. Not bad, but certainly not super tight.
I was wondering if I NEED to install an hrv (it was a recommendation by advisor). If i was to install one it would involve ductwork/bulkheads which i am not to keen on or to go with several lunos systems (or similar) which could get very pricey and retrofit many holes in my envelope.
Any thoughts or ideas would be greatly appreciated, thanks!
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Replies
Jeremy,
The short answer is: Yes, a house like yours needs a mechanical ventilation system.
A more nuanced answer would be: It's your house, and you can do whatever you want. The signs of a poorly ventilated house are the following: Moisture on the windows during the winter; indoor smells; and a vague feeling that the house is stuffy. If you notice these signs, your house probably needs ventilation.
If your house has a Panasonic bathroom exhaust fan -- in other words, an efficient, quiet fan -- you can leave the fan on for 24 hours a day when the house seems stuffy. That's a simple exhaust-only ventilation system.
Or you can live with your house for a year and see if you like it.
Thanks Martin
It looks like i'm going to have to come up with a strategy then. There are currently no bathroom exhaust fans so i was planning on installing those anyways. I am leaning towards a lunos e2 pair or lunos nexxt for the open concept main floor and a lunos ego in each of the 2nd floor (no basement). They just cost an arm and a leg here in Canada! However, If i went with a ducted balanced system, by the time get the duct design, equipment installed and commissioned the costs will likely be comparable.
Thanks for your input