Recessed lights have traditionally been costly contributors to heat loss. These fixtures allow conditioned air to leak into unconditioned spaces, such as attic spaces. The large rough openings needed to install recessed cans, the numerous perforations in the housing assemblies and trims, and the fact that manufacturers require a minimum 3″ gap between insulation and fixture made them extremely susceptible to air leakage. This air leakage increases substantially when the light bulb heats the air in the light fixture causing a chimney effect. Enough air leakage over a period can cause moisture problems and possible mold growth.
Sometime around 2002 all recessed light fixtures were required to have thermal protectors (these fixtures are called Insulation Contact). However, these fixtures were still manufactured with holes and perforations resulting in air leakage.
The image indicates bright areas around light fixtures are due to missing insulation and air leakage.
To address air leakage the International Energy Conservation Code (IECC), as of 2009, required that any recessed-can fixture installed in an insulated ceiling/attic must meet the air tightness standards and be labeled for insulation contact. The most recent requirements state recessed light fixtures installed in the building thermal envelope/attic space shall be airtight, IC rated, and sealed to the drywall.
By employing thermal imaging, we can determine the extent of energy loss around recessed light fixtures. Thermal imaging can also determine if moisture is present due to condensation.