Vent extesion

[jolenemarie]

Another HVAC duct problem in our basement remodel....

Wee need to open at least two new vents in the basement. There were already two with no return. We need to extend the duct after cuttting the new vent since after boxing in the ducts in the ceiling we have a 3 inch gap between the duct and the drywall. Did not find anything in the hardware store that works for this...is there an option out there besides making this custom? We found a vent starter in the hardware store but it was 3.25 by 10" and there are no vent covers that fit 3.25 width.

Another question...do we need to open a return? If so does it matter how close it is to the furnace?

Thanks you again!

[HandymanTrainer]

The extension collar you need is usually made on site, since the various lengths necessary are hard to predict. If your basement is sharing air with the rest of the house its probably not too critical to install a separate return for the basement, however, a small, register sized vent between the two floors close the the furnace will greatly improve air flow in your basement.

HandymanTrainer

[jolenemarie]

I thought that was probably the way it was done. I saw the pieces in Hone depot (during what has become our usual evening trip since teh remodel started!) I just could not figure out how attach the piece of duct once I cut the right length... I guess I can notch each corner 1"-2" and fold it out to have a surface to attach to the original duct then attach with sheet metal screws and tape.

[HayZee518]

Sheet metal ducts are fastened together using S cleats and 1/2 inch drives. These are just pieces of galvanized formed into an S and what is illustrated on my drawing. S cleats can be made or bought - same as the drives.

[jolenemarie]

I have used s-cleats, sheet metal and pre-fab parts to make repairs before...but this time I think I am calling someone who knows what they are doing. I'll watch them do it and I bet I'll be ready for next time. I will let y'all know how the project goes.

Thanks!