If you have standard recessed lamps in the ceiling under the attic, it is important to be mindful of the insulation you place above them. These lights generate a lot of heat, which could potentially set fire to the insulation and cause a fire in the house. To avoid this, make sure to keep all insulation at least 3 inches away from recessed lamps. Note that this warning only applies to standard recessed luminaires without integrated circuits.
Most attics have an access panel, hatch, folding door, or folding ladder. It is essential to insulate these access openings to prevent warm air from entering the attic. Some of these openings can be quite large, ranging from 8 to 10 square feet. This can lead to significant heat loss if not properly insulated.
The United States Department of Energy recommends having between 13 and 18 inches of insulation for an attic in order for it be properly insulated. It is usually installed with an electric fan and a long hose, but you can also spread loose pieces of insulation across the attic floor with your hand or with a leaf rake. The following map shows the recommended R values for attic insulation in eight different regions of the United States. Keep in mind that there are R values for uninsulated attics and also for attics that are currently 3 to 4 inches thick.
Attic ventilation grilles are usually installed on the ceiling, along the bottom of the eaves, along the ridge, at the top of the roof, or at the gable ends of the house. If your attic is already insulated, check if there is a paper vapor barrier or a polyethylene barrier attached at its lower part. Insulating your attic with fiberglass blocks or rolls is economical and generally easier than blowing cellulose with a loose filling. Since much of this work requires crawling or squatting, it's often best for an insulation company to add attic insulation.
As an expert in attic insulation, I recommend that you install insulation at the correct level your home requires in order for it be comfortable and efficient. You could simply place the insulation on top of the access opening, but then you would have to push it out of the way and put it back in place every time you enter the attic. Generally speaking, regardless of where in the country you live, you should have between 14 and 16 inches of insulation on the attic floor. However, since attics can become dangerously hot during the summer, this means finding a mild period between summer and fall for installation.
In addition, inadequate insulation in the attic can cause stifling heat in the rooms below, putting an excessive load on the air conditioning system and consuming more electricity. To ensure your attic is properly insulated and comfortable, use the table and climate map below to determine what level of insulation is best for your home based on your climate zone's R-value requirements. With proper installation and maintenance, you can enjoy a comfortable home all year round.
