The piece of duct must be notched for the mounting brackets and the electrical wire running from the junction box to the light housing, these edges are going to be sharp, so they should be covered with duct or electrical tape.
The notches go through to the bottom, where the duct meets the upper portion of the ceiling drywall, that means that unless an attempt is made to seal the notches in some manner, using more tape or caulking, loose fill insulation can get between the duct pipe and the light housing.
- The third method is to build a box approximately 20 inches long that goes over the top of the recessed light fixture and creates dams on both ends. This in effect is the same as building dams and putting a lid on top. While the lid, may allow some insulation above the light fixture, it creates a heat build-up problem within the box. For this reason the box parts should be lined with drywall.
If you are going to go to that much effort and expense you may as well replace the light fixtures with IC and ASTM ratings.
UPDATE
There is now a 4th method that can be successfully implemented to insulate around non IC recessed light fixtures.
Three new products are now available that provide a protective covering for non IC recessed light fixture so that homeowners can conveniently install insulation in their attic:
- TENMAT FF135 Recessed Light Cover (our favorite)
The TENMAT FF135 Recessed Light Draft Stop Cover is a fire resistant enclosure that was specifically designed to protect your light fixture from insulation in the attic and to stop unwanted airleakage through your recessed light. The FF135 has been tested in accordance with UL1598 for usage with IC and Non-IC rated recessed lights. TENMAT Recessed Light Covers allow the insulation to be continuous and uninterrupted over the whole area of the ceiling, therefore saving energy and carbon emissions. The FF135 covers are fit within seconds and do not require assembly or special tools. Simply put the flexible and lightweight cover on top of your light fixture - Done Deal! Benefits: -- Fire Safe -- Reduces heat loss through the light fixture. -- Limits the amount of cold or hot air entering from outside. -- Prevents insects and other small animals from entering through the light. -- Keeps insulation away from standard recessed lights. -- Easy fitting - can be fitted in seconds - no screws, drilling or assembly required. -- Enhances the acoustic protection of the ceiling. -- Maintenance free.
Ordering information for the Tenmat FF135 Recessed Light Cover.
Figure 5 - TENMAT FF135 non IC recessed light fixture cover
Figure 6 - TENMAT FF135 recessed light fixture cover in service
- CanCoverit
More than a recessed light cover that provides an effective barrier between recessed can light fixtures and insulation in your attic, the CanCoverIt™, as shown in Figures 5 & 6, safely improves can light energy efficiency up to 98%.. The unique design prevents your home's heated or cooled air from escaping into the attic and safely vents away excess heat away from the recessed light fixture. It's an inexpensive, fast and easy solution for complete attic insulation and eliminates the cost of removal and replacement of existing fixtures. CanCoverIt installs in minutes and provides a lifetime of money saving energy efficiency to meet today's green home improvement requirements.
Ordering information for the CanCoverIt.
Figure 5 - Closed CanCoverIt non IC recessed light fixture cover
Figure 6 - Open CanCoverIt non IC recessed light fixture cover
- Owens Corning SmartCap
Make your next attic insulation project that much easier by adding a SmartCap™ Attic Recessed Light Cover, as shown in Figure 7, to your list of hard working insulation accessories. The SmartCap™ Attic Recessed Light Cover is a pre-assembled, easy to install, fire rated recessed light cover that simply unfolds into a perfect cap over non-IC rated light fixtures in the attic. Folds-out into position between attic joists running parallel to joists to easily cover both the light fixture and its accompanying electrical box. Designed for non-IC recessed light fixtures with a nominal diameter of 7" (178 mm) or less. Allows attic insulations to achieve R values in excess of R-60 with maximum insulation heights as high as 24".
Ordering information for the SmartCap™
