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10 Ways to Cool Your Roof


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Rock on!

Ballasted roofing systems are roofs in which a membrane is laid on the roof deck and held in place by the weight of concrete pavers or natural stones, such as river stones. While ballasted roofing systems don't meet current Energy Star guidelines for cool roofing options, they do meet the "cool roof" standard for Chicago, which has been one of the earliest adopters of rooftop gardens and other green roofing technologies.

In a ballasted roofing system, the same stones that hold the roof membrane in place also provide an insulating barrier against solar heat, much like an adobe building in the desert or an old stone farmhouse that stays cool inside thanks to its thick stone walls. Ballasted roofing systems are relatively inexpensive, and ballasted areas may be combined with rooftop gardens to reduce the overall cost per square foot of a landscaped roof [source: Hoff].


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