HVAC Diffuser installation
Hi, the PO of our house finished the basement with a dropped ceiling. They ran HVAC ducts in several places, but did not bring the duct and diffuser flush with the ceiling tile. Not sure why they didn’t but I’ve attached photos to show. The HVAC was probably run before the basement was finished, but they didn’t spare expenses when doing the basement, it was a nice remodel.
Any suggestions on the easiest way to mount a diffuser in the ceiling tile? My thought is remove the existing diffuser, sheet metal register box. Then use flex ducting to go from the sheet metal duct through one of the ceiling tiles, then add a circular diffuser flush mounted to a ceiling tile. The hardest part may be getting the sheet metal register box out from behind the grid work.
Replies
Take a look at HVAC diffusers built for suspended ceiling applications.
You can get in several sizes, and then connect with flex duct.
the other option I'm considering is to use egg crate material and cut to the size of the existing diffuser and drop in the ceiling.
Whatever you do, the performance will be much better if your HVAC has a properly sized air return in the basement space.
You can also just drop egg crate in for a panel or half panel or couple places. Up to you what looks good. This will have a bit more drag than proper components, but may meet your needs for heat transfer.
While you are up there, if that is an outside wall, you might think about sealing and insulating the rim joist at some time.
Looking more at the duct and thinking. The easiest answer might be to cut the 6 inch duct about 2 feet back from the register box. Abandon the old register and not try and remove. Add a 6 inch circular diffuser to the ceiling tile to right of the duct, there enough room with the joist spacing to center the diffuser in the small square of the tile, and use a 6 inch to 8 inch reducer, and 6 inch flexible duct to go from the rigid sheet metal duct to the diffuser. There is easy access to do all. Materials less than $50. I have an M12 Sawzall that will cut the duct.
https://www.lowes.com/pd/IMPERIAL-6-in-White-Round-Air-Diffuser/5001872263
https://www.lowes.com/pd/Lambro-6-in-x-96-in-Aluminum-Semi-rigid-Flexible-Duct/3240913
@unclemike42 : the rim joists are insulated with fiberglass around the perimeter of the house, you can't see from the photos.