While most people think about installing attic insulation in the fall, insulation works equally well in the summer to keep hot attic air temperatures from penetrating the attic ceiling. Well-insulated homes should have a minimum of eight inches of ceiling insulation. Insulation is easy to install with just a few precautions. Make sure to cover exposed skin, especially when using fiberglass insulation. Also, be sure to wear a dust mask to prevent breathing in fiberglass particles and wear safety glasses to protect your eyes. If doing the attic insulation job in the summer, start early in the morning and quit well before the sun heats the attic to uncomfortable temperatures.
Attic fans, mounted on the roof, are important when cooling your home by reducing the temperature of trapped warm air in the attic. If the attic is cooler, the house temperature will be lower and air conditioners will not have to work nearly as hard to keep the home at a comfortable temperature. Attic fans are inexpensive and run by a thermostat, which turns the attic fan on automatically whenever the attic temperature gets hot.
Drafty attics, not drafty houses, make for very efficient heating and cooling. In fact, a well-ventilated attic should be as close to the ambient outside air temperature as possible. To achieve this, most homes should have a combination of ridge and soffit vents. The ridge vent, mounted along the entire peak of the roof, will allow trapped warm air and moisture in the attic to escape to the outside.
To make this happen however, lower vents must be added at the "soffit," which is at the underside of the roof overhang. With these vents installed, air is pushed into the soffits, rides up the underside of the roof sheathing, and exits the home at the ridge.
The nice thing about an attic ventilation system is that it works year round. Unlike attic fans, which run only in the summer and cost money to operate, ridge and soffit vents work together to take out hot air in the summer, cooling your home, while taking out trapped moisture in the winter, which can cause insulation to become damp and inefficient.