VENTILATION & INSULATION – what do they do?
How do the three work together? When each system performs it’s own job properly it creates an efficient energy saving system that protects and keeps your home comfortable. What does each one do and how does it work?
Picture above: As the hot air in the attic exhausts out of the roof; cool air outside is pulled in to fill the void. This creates a natural ventilating system using three (3) natural sources: air pressure, the thermal effect, and diffusion.
The Goal: An optimal ventilation system is designed to try and get the attic temperature the same or relatively close to the same temperature as the air temperature outside. Example: If it is 100° F outside you want your attic to be 100° F not 180° F. Meanwhile, the insulation in your attic (see the picture above) keeps the hot air from penetrating the living area inside, and keeps the cool air inside from escaping the living area.
The Prize: The two systems – Ventilation and Insulation work together to keep your house cooler in the summer and warmer in the winter, hence, saving you money on your energy bills year around!
Will this make my house colder in the winter? No. When air enters your attic in the winter it does not get colder cooling your house down even more.
Why do I need ventilation in the winter? Ventilation keeps your attic dry. Natural moisture in the air needs air movement to keep from rotting out the trusses in your attic. In the winter ventilation keeps your attic dry and insulation keeps the cold air out; and the hot air in the house.
CODES: Codes are different in different counties and cities. Usually the ventilation codes are either 1/300 or 1/150. This means you need 1 square inch of ventilation for every 300 or 150 square inches of conditioned attic space. Check your local building codes for more information
Insulation codes are different as well. Old insulation codes were R19 (roughly 8 inches of insulation in the attic.) Since then they have gone up to R30 (approx. 12 inches) or R38 (approx. 18.5inches of insulation.) The more insulation the better. Insulation pays itself off quickly. It is estimated that roughly 40% of home energy loss is through the attic, with approx. 36% through the floor, and approx. 10% through doors and windows.
How does your choice of roofing effect this?
Here at Brazil Quality Roofing, Inc. we can design a ventilation and insulation system optimal for you. Feel free to contact us for a free re-roofing estimate at (916)357-5930!