White vs Green Roof- LBNL Study

“The work comes from a team at the Lawrence Berkeley National Laboratory in California that’s dedicated to studying how to keep cities cooler. Although team members knew both white and green roofs are better than traditional roofing, they wanted to get some hard numbers comparing the two. White roofs came out ahead in both improving global temperatures and cost, but both are good choices, the team wrote in a paper published in the journal Energy and Buildings.”

Most importantly don’t forget to ensure that your roof is adequately airsealed, insulated and flashing is installed properly to reduce conductive, convective heat gain/loss as well as prevent moisture infiltration.  If the building lacks insulation (especially if it has a vented roof cavity) and has unsealed top plates, pipe penetrations, fan roof curb penetrations, etc this should be upgraded first before working on the roof membrane.  You may find you have an oversized heating or cooling system after buttoning up the building’s envelope.

Read more: Cooler Ciites

 

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A grant from Walmart for an Eco-roof experiment

“It’s a rare opportunity to back up the rainwater absorption and evaporative cooling benefits of green roofs with data from a real world application, said David Sailor, director of Portland State University’s Green Building Research Laboratory. PSU received a $133,000 grant from Walmart to spend the next two years tracking and comparing data collected by a rooftop weather station and sensors placed throughout the North Portland store’s roof.”

Read more: http://djcoregon.com/news/2013/12/16/eco-roof-experiment-on-aisle-five/#ixzz2niRrwLj0