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.
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View Comments
Is the Tenmat cover a good way to go with the new non-retrofit LED fixtures made buy WAC Lighting? I see no way for the heat from driver cooling fins on top of WAC fixture to get out.