Bertram31.com General Bulletin Board

Re: A/C duct work?

Posted By: Alex Moore
Date: Monday, 11 April 2005, at 10:26 a.m.

In Response To: Re: A/C duct work? (ken waters)

On the positive side, PVC will have almost half the friction to air flow than flex duct. Plus, the connections will be more air tight.

On the down side, insulating the PVC will be a pain. Even with foil-backed fiberglass, you have to get a good air seal at every seam or hot moist air will find its way to the cold duct and the resultant condensation will trash the insulation over time. To do it right, you need to use staples, ties, and mastic, not tape (all while on your back inside a cabinet!).

An alternative might be two-part polyurethane foam insulation. It's like the cans of "Great Stuff" foam you get at Home Depot, but will stick to a vertical or overhead surface. It also sets up in about two minutes vs hours for the one-part Great Stuff. Its pretty expensive, but you check it out at www.fomo.com.

If you're interested, I know a vendor in Richmond, VA, and one in Ohio who will ship.

Messages In This Thread

A/C duct work?
JK -- Sunday, 10 April 2005, at 8:02 p.m.

Re: A/C duct work?
ken waters -- Monday, 11 April 2005, at 7:21 a.m.

Re: A/C duct work?
Alex Moore -- Monday, 11 April 2005, at 10:26 a.m.

Re: A/C duct work?
Rawleigh -- Monday, 11 April 2005, at 2:02 p.m.

Re: A/C duct work?
Alex Moore -- Tuesday, 12 April 2005, at 7:17 p.m.

Re: A/C duct work?
Vic Roy -- Tuesday, 12 April 2005, at 10:44 p.m.

Re: A/C duct work?
Michael Mavromatis -- Monday, 11 April 2005, at 11:07 p.m.