A Michigan State University study recently found that the area covered by green roofs increased 80 percent in 2006 compared to the year before. Green roofs which are comprised of plants and other materials crucial to their growth are growing in popularity however cost remains a barrier to the spread of green roofs. Costs are twice as much as a conventional roof but last two or three times longer. As well, green roofs are heavier than traditional roofs and can therefore be problematic for existing structures.

But, green roofs do provide several benefits, including the ability to reduce cooling costs by as much as 50 percent and they retain stormwater.

Read the full story at Greener Buildings

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