James writes from Short Hills, New Jersey: "I have some ceiling lighting fixtures. The top of those fixtures are in the attic and are sealed metal. Can I lay Owens fiberglass insulation over those light fixtures without risk of fire? Or is it best to leave the top of those fixtures uninsulated? Also, what is the best way to add insulation to the attic? Can I lay another layer of insulation to the attic "floor" or should I replace the insulation there with better insulation?"

Answer: Insulation should always be placed three inches away from recessed lighting fixtures unless the fixture is marked "IC" (insulated ceiling). If insulation is placed over an unrated fixture, it may cause the fixture to overheat and perhaps even start a fire.

If you have existing insulation there is no need to remove it. We suggest adding new unfaced insulation right on top of the existing insulation. If the existing insulation fills the floor joist, we recommend placing the second layer perpendicular to the first.