Exterior ducting to package unit. Add insulation?

[INTMD8]

Does anyone have any input on adding insulation to exterior ducting?

The ducts are internally insulated, looks like about 1/2# thick material.

Would it help significantly to spray foam the exterior of the ducts, or some other type?

Thanks!

 

[Slowgsr]

I would. Wouldn't hurt

 

[dreasoner]

How does insulation board compare with the spray foam in terms of R value. The board would make a neater installation and could be painted so it was less obtrusive looking.

 

[kj_mustang]

Closed cell spray foam will degrade over time from UV light. It should have a protective coating.

 

[purplezr2]

Foam board will also degrade over time due to light

 

[pseudorealityx]

For commercial application exterior duct work, I typically call for minimum R-8, 2 coats of mastic, and a protective aluminum jacket that's built to prevent pooling of water.

 

[Mr onetwo]

For commercial application exterior duct work, I typically call for minimum R-8, 2 coats of mastic, and a protective aluminum jacket that's built to prevent pooling of water.

Plus 1 on that. I know this is against GJ spirit, but this is a job for a professional. Call a commercial HVAC insulation co. and get it done right! This is a small job and shouldn't cost too much.

 

[Highbeam]

Did they have to go vertical with that duct or could they have run it inside horizontal like the lower duct and maybe improved the looks and reduced the amount of outside duct?

 

[INTMD8]

Thanks for the info, didn't know there were commercial HVAC insulation companies.

I suppose the top duct could have went through at the same level as the lower duct but it would have then ran upwards on the interior wall.

 

[Brian_WK]

For commercial application exterior duct work, I typically call for minimum R-8, 2 coats of mastic, and a protective aluminum jacket that's built to prevent pooling of water.

And make sure they do all 4 sides with the jacket I have seen too many jobs where they just did the top and sides and left the bottom open and it makes a lovely home for critters.

Brian