A reader, Adam, recently asked about the pros and cons of using LED retrofits vs. sealing recessed lights from the attic. It’s such a good question that I had to write up a quick post detailing my thoughts on this important topic.

I’ll start by saying that I have upgraded all of the recessed lights in my home with LED retrofits. This has numerous benefits over attic sealing. Prior to good LED retrofits being available, I had constructed airtight/fireproof boxes installed from the attic, so I can comment on both methods from first-hand experience.

The retrofits were easy to do, taking maybe 10 minutes each, at most. These days, high quality retrofits are inexpensive, typically less than $30.

Benefits:

• Totally air-tight when installed properly with a good gasket
• Energy efficient – depending on your electric cost, the light will pay for itself, especially if it’s in a high-use location, like the kitchen. Usually less than a year.
• Energy efficient part 2 – you can insulate the attic properly above the fixtures. LEDs generate much less heat than incandescents. Plus, you won’t lose the heat from air escaping through the housing.
• Long lasting – quality LEDs are rated to last about 2-4 years running continuously. Compare this with an incandescent which has a life only one-tenth as long. This is much more convenient (less time on the ladder is safer too!). For most uses, that means you’ll never have to replace a bulb.
• The light quality of “good” LEDs is very natural if you buy high CRI (color rendering index) fixtures. This is very personal, so compare the light from different fixtures to find one you really like. I brought home several, installed them and then my wife and I could see how they looked in our own homes which is much different than the display case in the store. You can usually return the ones you don’t like, so it’s worth trying a few.
• The retrofit itself is quite simple usually. Most wire into your existing fixture using a screw in connector that replaces the existing bulb.
• Air/moisture leakage through recessed lights are one of the primary sources for mold and rotten roofs. By installing air-tight LED fixtures, you will potentially prevent a very expensive roof replacement and mold remediation.

Challenges with retrofitting from the attic:

A picture is worth a thousand words…

• Working in attics is not fun. It’s hot, dusty and access is often difficult. This makes contractors less likely to do a good job because they’ll be anxious to work quickly and get out of there.
• It can be difficult to mount the air-tight enclosure in the attic given the construction of a typical recessed light fixture. This often leads to compromises that leave gaps, defeating the purpose of an air-tight enclosure.
• Incandescent lights generate a lot of heat. Some older fixtures aren’t rated for enclosure. Usually this isn’t a problem however.
• Covering the fixture with a housing can make insulation challenging. Most contractors are afraid of insulating around fixtures, leading to compromised insulation.

Other considerations:

• Some LED lights are not-dimmable – so make sure to buy the right type if you need them to dim.
• The convenience factor of not having to replace bulbs in high ceilings is worth a lot.
• Make sure the chosen fixture is the right size (4″, 5″ or 6″) for your retrofit. There are also different mounting styles that can affect compatibility.
• Avoid off brands or those without a good warranty. The only trouble I’ve had with LED bulbs/retrofits are with cheap “knock-off” type. My favorites have been manufactured by CREE, which were the pioneers in LED lighting. Phillips also makes quality products.
• You still have to be careful in sealing the retrofits in order to make them air-tight. They need to have a good gasket and be firmly seated to the ceiling.
• The thermal image, below, shows a huge amount of air leakage around a so-called air-tight recessed light fixture. As with all things in home construction, installation is key!
• For best air-sealing, I have used foil-tape to seal the holes inside the existing fixture. Some people claim you need air flow through the fixture for cooling but the fact that these fixtures are built to be air-tight negates this argument.

Air-tight? Not unless installed right!