Recessed lighting is wonderfully flexible but can affect your HVAC efficiency. Besides spotlighting artwork, you can target a desk or other workspace, border a room, or mix it with lamps or other lighting methods to create a desired “mood.” The nice thing about recessed lighting is it’s unobtrusive. In a house with lower ceilings, it can be particularly nice to have recessed lighting instead of ceiling mounts which can make a room feel even smaller.
The problem with it is most people don’t realize that the tradeoff is less energy efficiency in their home. Recessed lights are tucked up into the ceiling. The housing that holds the bulb is located above the ceiling material, which offers a sleek look, but requires a large hole in the room’s envelope. That leads to drafts, and in the summer time here in Florida, that lower efficiency can mean a much higher electricity bill than you bargained for because recessed lighting causes substantial conditioned air leakage into your attic.
Recessed lights penetrate into your attic space. Any household energy auditor will tell you that recessed lights are among the most notorious energy wasters in modern homes. Auditors often use thermal mapping technology to see exactly where air leaks are located, and these fixtures often stand out as the biggest HVAC efficiency problem in the room.
In fact, Richard Rue, Chief Engineer at EnergyWise Structures (who has engineered over 40,000 Ultra Energy-Efficient homes), says, “recessed lights that penetrate into the attic space can be the “kiss of death,” unless you’ve insulated the attic with sprayed foam. One of these seemingly innocuous little lights represents one square foot of uninsulated attic space, and 20 of them is equivalent to having a door open in the attic at all times”.
Unfortunately, there are no simple tricks to address this problem. But if you’re willing to invest a little effort, money or both, you have a range of options to reduce or even eliminate the energy loss. The first task is to determine what type of recessed light fixtures you have and how they’re attached to the ceiling (if you’re lucky enough to be in the process of having these light fixtures installed, make sure you check what type of lights they are before they are installed). If you don’t already know this, you should ask an electrician for help inspecting your lights.
There are two types of recessed lights: insulation contact (IC) and non-insulation contact (non-IC). Non-IC lights get too hot to be in direct contact with insulation material, which means these lights often have the worst air leak issues, so avoid them if you can. IC fixtures are lower wattage and produce less heat, which means it’s acceptable to pile insulation material over the light housing.
You’ll also want to check how the light is affixed to the ceiling. Ideally, you want a tight caulk seal attaching the light directly to the ceiling material. If it’s merely bolted or wedged into place, you know air is getting through. Just one drafty recessed fixture can result in air loss of up to 2.5 million cubic feet per year, wasting up to 1 million BTUs during that same period (BTUs, or British Thermal Units, is the standard by which power is measured). If all you want to do is improve the seals around your lights, all it will cost you is a little caulk — but your efficiency boost will be minimal.
Many recessed lights are now completely sealed, resulting in significant energy savings. You may want to upgrade your fixtures altogether. If so, make sure you choose IC fixtures that are fully sealed and of course choose insulation contact fixtures. When you have them installed, be sure to get a tight seal and cover the tops of the fixtures with plenty of heat-resistant insulation. And be sure to have them installed by a professional electrician. You can also have your HVAC contractor check the attic installation to be sure they are as energy efficient as possible.
For this and all of your HVAC needs, contact At Your Service at 239-565-9433.