Recessed lights generate lots of heat. In fact, some operate at temperatures up to 200°F. In the uninsulated attics of many old houses, these fixtures may work for years without incident. Problems start when a contractor insulates the attic, usually as part of a larger renovation. If you pile insulation on top of a recessed fixture, there's no way for the heat to dissipate. As a result, the framing and other combustibles around the fixture can get hot enough to catch fire. That's why building codes require attic insulation to be held back from recessed lights. Most codes follow the "3 to 4 rule" — they specify a clearance of between 3 and 4 inches (check your local
