Summer Home Improvements for a Cooler Attic

Attic insulation comes in many forms: expanding foam, rolls of fiberglass, loose-strewn “pink” fibers and blown-in cellulose made from recycled paper. Some of these are installed under the roof deck, others on the attic floor. Having insulation in the attic helps reduce the radiant heat absorbed through the roof. While no attic insulation has the capability to prevent 100% of radiant heat from passing through, it can be combined with other components to further reduce the heat that eventually reaches the attic.

The term “cool roof” applies to reflective roofing systems, which are common on flat commercial roofs. These roofs have white or light-colored surfaces that reflect sunlight, including invisible UV radiation and solar heat. It’s like how wearing a white shirt under the sun feels more comfortable, compared to wearing a dark-colored shirt: only a fraction of solar heat makes it through the roof. A similarly-colored sloped roof may not be as aesthetically pleasing, but fortunately, manufacturers such as GAF offer asphalt shingle products with reflective properties.

Proper attic ventilation helps further reduce whatever heat makes it through to the attic. Heat tends to rise, therefore it collects at the ridge. We’ve seen roofs that sustained damage from trapped heat caused by poorly-designed ridge vents. Ideally, the ridges allow hot and moist air to be vented out. The resulting difference in air pressure pulls cool, fresh air in through the soffit vents. For homes with large roof areas, roof exhaust fans can be installed to bolster the ridge vents. These fans are powered through the house’s electrical system, but there are solar-powered options available.