View Single Post
Old 02-24-12, 07:07 PM   #5
herlichka
Apprentice EcoRenovator
 
Join Date: Oct 2010
Location: Simcoe County, Ontario, Canada
Posts: 102
Thanks: 11
Thanked 15 Times in 10 Posts
Default

I have actually just completed doing exactly this job for a customer. The potlights are about 25 years old in a cathedral ceiling, and were equipped with 75w incandescent flood lamps.

The first part of the upgrade involved a combination of foil tape and duct seal compound packed into the corners and crevices. Then I installed a layer of self adhesive foam insulation with a foil face. These particular fixtures consist of a galvanized box with a cast aluminum reflector and trim ring, so the insulation was relatively easy to install.

The second part of the project was to replace the lamps with dimmable CFL floods, aside from the energy savings they operate much cooler and set up a "less intense" convective air flow through the fixture and into the insulation.

I personally don't like seeing pot lights in an insulated ceiling, the continuity of the insulation and vapour barrier always seems to be a compromise, not because it's overly difficult to do, it's because no one seems to take responsibility for doing it right: the electricians don't worry about it, the insulation guys shrug their shoulders, and even most Building inspectors don't look too hard. There is also confusion about the definitions, many cans are suitable for direct contact with insulation, so people assume that they are vapour tight when in fact "vapour tight" is a distinct and separate specification.

The reason we did this work on these lights is because, as I mentioned, these lights are in an insulated cathedral ceiling, and the hot air travelling through them warms the roof and shingles and melts the snow. You can actually see the location of each and every light in the house. The snow melt causes a serious icing problem at the eaves.
This is the first step, and is moderately succesful. The next project is a new steel roof, complete with a new layer of insulation to be installed later in the spring of this year.

Last edited by herlichka; 02-24-12 at 07:11 PM.. Reason: Spelling
herlichka is offline   Reply With Quote