Dust, mold, and wiring in return air wall cavities
Unsealed return air cavities pull existing dirt and basement mold directly into your home's air circulation. Cutting into these walls to install network boxes creates new openings for contamination and requires special plenum-rated cables if you don't add proper ducting.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Cleaning up the return duct and using foam seal or spray foam on corners and drywall to prevent dust entryDid this help you?
- 2Installing rigid pink foam board on all sides and top to create a clean plenum and keep wires containedDid this help you?
- 3Mounting the box and using caulk to seal any wall penetrationsDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I want to install a flush mount network box on the other side of one of these walls, but I dont want to introduce a place for contamination to come in.”source ↗
“And the existing dirt is what go me thinking about ducting it in the first place. Plus I was worried about adding wire, and making sure what I add is plenum rated if I dont add ducting.”source ↗