New roofing material could let builders roll out the 'green' carpet

Summer may be coming to an end, but there may still be time for home renovations - starting with a little bit of grass on your roof.

Researchers from Toyota Roof Garden in Japan are now taking orders for grass tiles, called the TM9 turf mats, to help reduce urban heat island effects and cool down metropolitan areas.

The urban heat island effect is the name for the phenomenon of densely populated urban areas having significantly higher temperatures than surrounding areas. Concrete, which holds heat, is seen as a large contributor. Cities can combat the problem with green spaces - and increasingly green roofs.

Green thumb, meet handyman
"Green roofing", as it has been dubbed, is made up of vegetation, a growing medium, a filter layer, a drainage layer, a root resistance layer, and a waterproof membrane.

This combination will allow water to effectively drain straight into the roots of the grass, making the mats easy to maintain.

TheTM9 mats incorporate all this growing technology in twenty-inch square tiles, two inches thick. They're made from a special brand of Korean velvet grass that only needs to be cut once per year.

The price is a lot steeper than your typical asphalt shingle at $43 US per square yard.

Green roofing has been a widely discussed topic among environmentalists over the years, and has sparked many citywide projects in efforts to build more "greener" communities.

In Canada's biggest city, officials have proposed the Green Roof Pilot Program, which will showcase a variety of green roof types to encourage this type of construction in Toronto.

City officials are putting aside $200,000 of Toronto's Water budget for green roof construction, offering grants for up to $10 per square metre to all those looking to build their own green roofs.

York University, one of the largest institutions in Toronto, added a green roof to its computer science building in 2003.

Photography: Garden Visit

Source: Discovery Channel Reports, August 28 edition