Duct Sealing - Proper Steps Needed

HyperX

Hello Expert DIYers,

I recently bought a home (25 years old, in Rochester, MI) and spent a summer and a winter in it.

The family/living rooms (1st floor) get enough hot/cold air. I'm happy there.

The rooms in 2nd floor do not get enough hot/cold air, mostly due to the unit being present in one corner of basement and the master bedroom being 2nd floor in exactly the opposite corner.

I also noticed that the area where the furnace is present is much hotter (in winter) /cooler (in summer).

So, I bought UL181 Mastic, UL 181 Foil Tape to seal ducts.

I saw numerous YouTube videos and followed many threads and could not find an answer to this.

1) I'm applying mastic over the duct joints. Do you put the foil over wet mastic or after it has dried?

2) How do you reach the inaccessible areas on the duct (on top of the duct)?

Thanks!

Adam_M

Tape is ok, but If the surface is not clean it can peel away. A sure way is using duct sealer its a grey sticky product with the consistency between paint and caulking, use a small paint brush to apply it, once it's on your air tight.

As to your two questions apply tape when the surface is dry. Also to apply in tight spots use a Long narrow stick like a cedar shim or wooden paint can mixer stick, as long as the tape is wider then the stick you can bend the tape around the stick then apply it and smooth it out with the stick.