Wandering through the streets of Berkeley, you may not be looking up very often. Maybe you’re focused on tracking down that one thrift store you’ve been meaning to find, or focusing intently so as not to spill your boba. Well, looking up has some rewards in Berkeley. Two words: green roofs.
Green roofs are flat roofs that have been adapted to house plants. They can be used for a variety of purposes: cooling systems, urban farming and simply enjoying the view.
Now, I’ve met some green roof skeptics in my life, but the benefits of these roofs really outweigh any possible cons. For one thing, green roofs may just be the solution many cities need for global warming. They help combat the urban heat island effect by adding vegetation to the area. Buildings and pavements absorb heat, and this can be a serious problem in cities. Adding green spaces creates a cooling effect. In some cases, it can lower a city’s average temperature by up to five degrees.
Green roofs create a cooling system for the buildings themselves, thus decreasing or even eliminating the need for air conditioning. On the flip side, they provide insulation for the roof during colder months reducing the need for heating. With less need for air conditioning or heating in buildings, a city’s energy costs and consumption could go down by a lot. You could thank the plants for cooling the surrounding climate.
Another big plus is stormwater management and the lifespan of the roof. According to the U.S. National Park Service, a well-maintained green roof can almost double the time before a standard flat roof needs to be replaced.
At this point you may ask yourself, “Why hasn’t everyone started sticking grass on their roofs?” This is where a twist comes in: white roofs. These cheaper alternative to green roofs are made of bright white material to reflect as much light as possible. According to Art Rosenfeld, an Emeritus scientist at Lawrence Berkeley National Laboratory, “White roofs are three times more effective at countering climate change than green roofs.” Furthermore, white roofs cost nine dollars less over a span of 50 years than green roofs.
Also called cool roofs, white roofs were given a stamp of approval by the state of California and are now increasingly being implemented in building codes. These roofs have also been mandated in Chicago, New York, Seattle and Philadelphia.
Although white roofs do reflect sunlight and act as a cooling mechanism for buildings, there is a cost. In their research published in Journal of Climate, researchers Mark Jacobson and John Ten Hoeve said that by reducing the amount of solar heating on a surface, the temperature difference between the surface and the air decreases. Temperature difference is what controls cloud formation. With less clouds, there is more sunlight and the heat problem grows.
What’s the solution to these surface warming problems? The best of both worlds: a combination of both green and white roofs. With green roofs, we get perks such as more possibilities of green spaces being incorporated into cities, which provide mental and physical health benefits. With white roofs, we get fast-acting solar reflection that cools cities.
Now, to bring it back to how this relates to our own backyard: Berkeley has quite a few green roofs. I encourage you to check them out this summer.
Although they may be difficult to notice, there are green roofs atop the restaurant Comal in downtown Berkeley as well as above the Freight & Salvage performance venue. One very cool green roof is found on top of The Dwight, an apartment building located at the corner of Dwight and Parker streets. And, of course, I didn’t forget about the famous green roof atop the California Academy of Sciences in San Francisco. This roof, completed in 2008, serves as a home for 1.7 million native plants and an outdoor classroom and is certified by Leadership in Energy and Environmental Design (LEED). You can reach this magnificent view and environment by purchasing admission into the Academy.
Next time you’re taking a stroll through Berkeley, I encourage you to check out these roofs. Looking for a new apartment? Check out The Dwight for some green roof fun.