Replies

1. 
   HeavyDuty | Sep 05, 2005 09:05am | #1

   IC units are designed to be covered by insulation so I don't see a problem in your situation.

   Do you have enough space to fit an IC housing in the joist bay shared by the duct?It's going to be tight.

1. 
   BillHartmann | Sep 05, 2005 09:10am | #2

   I more concerned about the effect of the can light on the duct insulation.Never been around the stuff, so I don't know. But what is the temp rating of it?

1. 
   HeavyDuty | Sep 05, 2005 09:18am | #3

   Hmmm... I was assuming it was fiberglass. Now if that were some rubbery or foamy stuff, that could be a concern.

1. 
   Hayduke | Sep 06, 2005 12:58am | #4

   Spacing is not an issue. The big issue or uncertainty is the heat of the light against the plastic covering of the HVAC duct. I suppose that I could install some foil tape on the duct to protect it somewhat. Any thoughts?

1. 
   HeavyDuty | Sep 06, 2005 07:27am | #9

   Do you have flex duct or poly vapor barrier? If you can squeeze in about an inch of fiberglass between the plastic and the IC unit you should be fine. Or you can install one of those poly shrouds that is designed to provide a continuous VB for IC units which will give you enough spacing to the duct.

    

2. 
   BillHartmann | Sep 06, 2005 04:57pm | #10

   Yes, I think that is the best, just a little thermo isolation between them.

3. 
   Hayduke | Sep 07, 2005 12:59am | #11

   Yeah, it's the flex duct with the plastic outer sheathing which ultimately was my concern.  I looked up the product online, but it didn't have any temperature rating.  My initial thought was to wrap the duct with reflective board and insulation tape for the width of the lamp which would certainly protect the duct.  I hadn't considered simply installing a width of fiberglass insulation between the two.  This solution may be the simplest. 

   Thanks for your thoughts.  Any more will be appreciated.

2. 
   DanH | Sep 06, 2005 03:44am | #5

   IC lights are rated for contact with most forms of insulation. (I presume this includes cell and styrofoam, but read the data sheet.) If they're rated for contact with regular insulation they should be fine with duct insulation,

1. 
   BillHartmann | Sep 06, 2005 04:34am | #6

   They are rated so that the fixture does not overheat.I hve no idea if they test the affect on insulation.And in typical adic insulation they would not have any affect.But I have no idea what temp that the plastic used on the heating ducts can withstand.

1. 
   DanH | Sep 06, 2005 04:53am | #7

   Well, I would guess that heating duct insulation has to be fireproof, at least in commercial applications.

2. 
   custombuilt | Sep 06, 2005 05:18am | #8

   IC's can are rated for contact with most forms of insolation----dunno about the plastic rapped stuff on the duct.  I take it that you have flex duct?

   I would proply go with your idea to rap the duct in foil tape for a foot or so, when it was right up against the fixture.  ICs aren't supposed to get very hot, but it would never hurt!When in doubt, get a bigger hammer!