How critical is sealing seams (not joints) on dryer ducting?
I’m in the Pacific Northwest (Climate Zone 4 Coastal). I just realized our dryer ducting (rigid) is sealed at the joints but not along the seams. Most of it is wrapped in insulation now, and it will be buried under loose fill cellulose soon. The seams are facing downward, too, unfortunately. How important is it that these length-wiser seams get taped? Should I go through the hassle of unwrapping (and annoying my GC) to tape them? The last thing I want is condensation in the fiberglass wrapping or cellulose loose fill.
The current duct insulation wrap on the attic portion also has substantial tears in the air barrier. Is that an issue?
More info on the duct: 4″ or 6″ diameter (can’t recall). It runs ~ 8′ up an interior wall, then elbows 90 deg along the attic floor for about 6′, then angles upward at ~ 45 degrees to a gable wall penetration (~ 4 feet above attic floor).
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If you are talking about the duct that has a locking seam you push together, when I googled this same question the consensus was that nobody tapes the seam and it is airtight-ish. I wouldn't worry about it.
It does indeed have the locking seams. Thanks! I couldn't find any good consensus with my Google Fu, but I did see some discussion of leakage dropping from ~ 10-30% to <10% after taping vertical seams... but it was very vague and un-cited.
Boy that aluminum tape sure is cheap.....
Sure is. The issue is not the cost of the tape. As I mentioned, it's the hassle of digging it out of insulation and annoying my contractor.