Is Your Roof Affecting Your HVAC System?

So many things about your home affect your HVAC system, and the roof has one of the largest impacts. It’s exposed to the weather 24/7 and its insulation, color, condition, and ventilation all determine its efficiency.

Insulation

Roofs aren’t built to reject heat gain and loss. It’s the insulation beneath them that does that. Air and water leaks undermine the energy efficiency of roofs and attics, and a tightly sealed and intact roof can turn an attic into an oven in the summer.

Color

A dark roof absorbs more heat than a light one, which makes it a poor choice for a home whose attic doesn’t have enough insulation. It’s as much a problem in the winter as it is in the summer. Ideally, an attic will be the same temperature as the outdoor air, even when it’s in the teens outside.

A warm attic in the winter causes ice dams that can lead to structural damage to your home. A cooler attic in the summer won’t tax your cooling system as much since less heat in the attic translates to a cooler home. When choosing new shingles for your roof, look for a product that has a 0.85 emittance rate. This means that the roofing material will reject 85 percent of the heat that hits it.

Condition

A leaking roof not only causes structural damage to the roof deck and the attic, but it also affects the HVAC system by damaging the insulation. Wet insulation doesn’t work as effectively and moldy insulation deteriorates and loses all its insulating value.

Ventilation

National building codes require a specific amount of ventilation in the attic. Fresh air flowing through it prolongs the life of the structural materials and moderates the temperatures. Look on the underside of the roof or the gable ends for vents. There should also be ridge vents at the peak of the roof to cross ventilate the attic.

Anything you can do to make the roof more energy efficient will reduce the burden on your HVAC system. To learn more, call Energy 1 Heating & Air Conditioning, offering HVAC services for Lorain homeowners.

Our goal is to help educate our customers in Lorain, Ohio about energy and home comfort issues (specific to HVAC systems). For more information about other HVAC topics, download our free Home Comfort Guide or call us at 440-201-2959.