Air-Sealing Can Lights Safely
Common air-sealing enclosures can lead to melted foam, shorted wiring, and even fire.
Synopsis: Using foam insulation is a common way to stop airflow through recessed can lights, which are notorious energy wasters. Unfortunately, the temperatures inside a foam enclosure can get hot enough to melt the foam or the wiring inside the enclosure, creating a fire risk. Veteran electrician and building-science expert Larry Armanda points out the potential dangers and shows how to seal up can lights safely and effectively. To determine just how hot it can get inside a can light enclosure, Larry constructed a purpose-built test rig and monitored the temperature inside with a four-channel data logger. Then using his temperature data, he designed a safer enclosure with modern wiring, a heat-resistant enclosure, and a long-lasting LED light bulb. Two detailed illustrations that complement the article show both a conventional can-light enclosure and Larry’s safer enclosure.
I’ve been an electrical contractor and a building-performance professional for more than 35…