Gone are the times that roofing systems were only a simple part of a building. Roofing systems are increasingly trending toward saving money and energy, and providing other environmental benefits. And this trend should continue.
White is the New Green
While in London in 2009, President Obama’s Energy Secretary Steven Chu, told his former colleagues at the Lawrence Berkeley National Laboratory that painting roofs white to reflect sunlight can make a huge difference to global warming.
“There’s a friend of mine, a colleague of mine, Art Rosenfeld, who’s pushing very hard for a geo-engineering we all believe will be completely benign, and that’s when you have a flat-top roof building, make it white. “Now, you smile, but he’s done a calculation, and if you take all the buildings and make their roofs white and if you make the pavement more of a concrete type of color rather than a black type of color, and you do this uniformly . . . it’s the equivalent of reducing the carbon emissions due to all the cars on the road for 11 years.”
The Wall Street Journal (WSJ) argues that “Secretary Chu actually understated the potential benefits of global whitewashing. The Lawrence Berkeley research he refers to (which we wrote about last fall) says that white roofs and pavements could mean a one-time reduction of 44 billion tons of carbon dioxide. That, Art Rosenfeld said, translates to removing all the cars in the world for 18 years.”
WSJ goes on to talk about the potential benefits of such a movement. “Reflective surfaces also reduce temperatures in urban “heat islands,” and reduce the need for air-conditioning, which in turn reduces the demand for electricity, which generates its own greenhouse-gas emissions.”
Gardens in the Sky
Putting gardens on rooftops is a fast growing trend. Vegetative rooftops mitigate urban heat by cooling and humidifying the surrounding air, creating a microclimate which has beneficial effects within the immediate area.
They create biodiversity, encouraging wildlife, such as birds, butterflies and insects to remain within urban areas. Plants and shrubs also filter out dust and smog particles. Just about any plant imaginable can be grown on a rooftop garden, including fruits, vegetables and flowers. Green rooftops also reduce noise levels and are most effective on buildings near airports, factories or busy freeways.
The Secret is in the Membrane
A Protected Membrane Roof (PMR), much like a garden rooftop, protects the roof membrane from climatic extremes and physical abuse, thereby greatly increasing the life expectancy of the roof. Often referred to as an “upside down roof,” a PMR’s temperature range is drastically reduced. In fact, the PMR system provides a thermally protected environment with conditions far superior to those endured by membranes before insulation was used between decking and waterproofing. By simply reversing the insulation and the membrane – insulation on top of the membrane rather than beneath – the cause of many roofing problems can be eliminated. Development of better roofing systems is ongoing, but PMR solutions are only getting more effective.
Make it Useful
Converting or designing normally unused roof areas into green roofs combined with usable spaces simply makes sense. Almost anything can be integrated into a rooftop, from walkways to benches to volleyball courts.
Most green designs include a park-like setting and there are many benefits beyond just environmental. Personal well-being is a significant factor in the design of the usable rooftop and people tailor these to their individual wants and needs.
A simple outcome of reclaiming the roof of a building and making it an amenity for buildings occupants is the increase in property value. And besides having a great looking roof, you feel good because of the positive environmental impact. These are just a few of the many ways roofing research and development is moving into the future.