In case you haven’t seen it in the news recently, another conspiracy and cover-up has been discovered and is being referred to as “Climategate.” It seems there has been some manipulation of the database of historical temperature data that has been used to support the concept of global warming. A string of emails between scientists has been uncovered that indicates there has been some manipulation and/or deletion of data that did not support global warming theories, bringing into question the validity of graphs and studies that suggest the earth is warming because of human activities.
So what does this have to do with cool roofing? Can cool roofing really influence global climate? Energy Secretary Steven Chu thinks so. Some studies have shown that cool roofing can indeed help reduce urban heat islands. This may be true, but given the recent buzz noted above, is the data in those studies also suspect?
There may be some influence on urban heat islands from cool roofs, but the real and practical proven influence cool roofing has is on energy usage. Science isn’t even necessary to prove to building owners that cool roofing reduces air conditioning needs. All that a building owner needs to do is open his or her July utility bill.
Savings in summer electricity use for air conditioning is real, and even if there is some heating penalty (the idea that white roofs will prevent a building from warming up in winter), that penalty is almost always less than the benefits from reduced cooling loads.