HRV duct – R value
Maxxxx001
| Posted in General Questions on
Hello,
Im planning to add HRV to house, located in Niagara Falls, NY
Duct will run in basement floor joists, is R8 flex pipe enough ?
thank you
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Replies
Is your basement part of the conditioned space in your home?
Flex duct can work, but most serious pros prefer rigid ducting, as it's very easy to get installation of flex duct wrong, and in many cases it results in reduced airflow.
The duct size depends entirely on your home's size, your duct layout, and the ERV specifications. 8" is usually enough for a trunk line, if that's what you're planning, but flex duct is not a good choice for a trunk line.
So my HRV has 5” ports.
I will mount it as per manual tying too my HVAC system.
I do prefer solid as well but there are limited insulation options
Thank you
If your basement is insulated and conditioned, you don't need duct insulation. If it's semi-conditioned--i.e., stays above 50°F or so, R-8 is probably fine. If it's cold--i.e., gets close to freezing temperatures--I would want more than R-8.
Can you provide dedicated extract ducts and just have the supply lines tied to the HVAC ducts?
5" ports doesn't mean the entire run has to be 5"; larger ducts have less friction.
I'm not an HVAC expert so I'll hold off on further commentary.