How to add ERV to townhouse
Hi All,
Pictures for context: https://imgur.com/a/sxaA5fO
I live in an interior townhouse, so only 2 exterior walls.
It’s not 100% needed, but I have been thinking of ways to incorporate an ERV or other means of fresh air exchange besides opening windows. Would help with CO2 levels when cooking or otherwise just hanging around in the main area where levels can get elevated fast without windows open.
The main problem is there just isn’t a lot of places to do it.
Given the layout, would the best option be to hook it up to the supply side of the central AC from the basement level, or is there some way that might be better for a through wall unit on the limited exterior wall space?
Note: currently don’t have an exhaust fan out of the house from stove, or in the bathroom, but will be installing a 110 cfm fan in the bathroom on the 2nd floor soon.
This might also be helpful for any others in townhouses with limited options for erv/hrv options.
Appreciate any suggestions!
Alex
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Replies
Best places for ducting termination are gables and rim joists. Town houses are challenging because often one or both are inaccessible.
There are small HRV units (Lunos) that come in pairs and sleeve into exterior walls, this may be an option for you.
I have to double check measurements, but I believe the lunos needs a specific clearance between walls and windows, which isn't there(sadly) otherwise they were the front runners.
You are right though that attic access is not there without cutting from beneath, and rim joist is hard to work in from the inside because the joists are running parallel to the exterior walls.