HVAC return air “box” materials/construction?
Nola_Sweats
| Posted in General Questions on
I need to rebuild my HVAC return air box, which is made of plywood covered by drywall. The drywall was recently water-damaged by a bad a/c condensate pan.
Should I use drywall again? Or foam board? FWIW, the box is in living space at floor level on the first floor, so it’s conditioned on all sides except the bottom, which has spray foam underneath. House is Zone 2A, hot-humid Gulf coast, with a 2007 heat pump.
Does it matter what the R-value is if it’s all in conditioned space? Is there a reason to use drywall instead of foam board? Should I replace (or cover) the undamaged drywall sides with foam board also? Thanks!
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Replies
Nola,
You are talking about the part of the system that houses the filter, correct? Theses enclosures are usually made of sheet metal or duct board. I suggest hiring an HVAC contractor to handle this task.
Yes, I'm referring to the box immediately behind the filter, where return air first enters the system.