That s what a recessed light does.
How to seal recessed lights in attic.
In fact you want to seal any hole in the ceiling that allows a path for warm moist air to go directly into the attic.
Sealing from below in homes where attic access isn t available or is difficult and for recessed fixtures mounted in first floor ceilings a top hat and insulation is not an option.
Seal the can lights.
Reinstall the bulb in the recessed light fixture.
If you have recessed light fixtures in your home you may also have a significant volume of conditioned air escaping into your attic.
After removing the old fixtures add insulation to the empty spots left in the ceiling install airtight electrical boxes and use the same wiring to put in surface mounted.
Press the trim ring into the caulking.
For more information see air sealing can lights safely fhb 249 the best alternative in your situation is to replace the recessed lights with nonrecessed lights.
Sealing can lights can be done by several methods.
To prevent heated air from escaping around the hole in the ceiling on recessed light fixtures.
Apply a bead of caulk around the cutout in the ceiling.
This video from green homes america provides a good overview of the air leakage issue with recessed lights and shows an actual top hat installation.
Remove the bulb from the light fixture.
The recessed lights in my house are accessible from the attic but there s no insulation around them because it says on the fixtures that they need to vent the heat generated by incandescent bulbs.
Pull the trim ring down a few inches from the ceiling.
You can stem the flow of air and money by air sealing your light fixtures from the inside with just a roll of painter s tape a can of spray foam insulation and a tube of painter s caulk.
Hole in your ceiling and add a 100 watt bulb enough heat to bake cookies and you have a recipe for huge heat loss as well as a major contributor to ice dams.
Check areas around light fixtures ceiling fans smoke detectors and air conditioning ducts and registers.