Every post this week has been about roofs, we looked at white, blue, and soy roofs. Let’s not forget about the classic green roof.
The classic green roof is tried and true with hundreds, if not thousands, of proven efficacy. Green roofs retain water, cool buildings, and improve the planet. When it comes to green roofs a new study has revealed that the bigger the installation the greater the effects a green roof has.
•Intensive green roofs achieve the greatest air temperature and PET reduction in the low-rise buildings.
•Green roofs reduce outdoor air temperature and buildings’ cooling energy above buildings up to 30 m height.
•Green roofs strongly reduce buildings’ cooling energy demand in the extremely dense built-up areas.
•Intensive green roofs attain the best impact on outdoor air temperature and buildings’ cooling energy demand reduction.
•Economic aspect favors the extensive green roofs usage to reduce cooling energy in the buildings.
Many of the eco-friendly roof options require upgrades to structures to support the extra weight. Building an blue, green, or even a white roof isn’t a solution for every existing building. For buildings with unsubstantial asphalt roofing what can we do? We can use soy! Shingles dry out when they degrade over time, currently oils are used to prolong the life of shingles. Instead of using nonrenewable oils a company has explored using soy based oils instead.
Organizers demonstrated Roof Maxx on Earth Day because it’s a green product made from 86 percent USDA biopreferred soybean oil. By restoring a roof instead of replacing it, the product also eases the strain on landfills. The EPA estimates about 13 million tons of asphalt shingles are discarded every year.
“If there’s an opportunity for recycling or sustainability, in my mind you should look into it,” Schafer said. “In the past, it was a lot more expensive sometimes… but as time goes on it’s more prevalent, it’s a little easier to do.”
For a good future we need to respect water at its source and in our built environments. You have heard of a green roof, a white roof, and now we have a blue roof. These roofs all have the same ultimate goal in mind: do less harm to (or maybe even better) their local environment. Blue roofs focus on water management and therefore a best located near wetlands and shores. Blue roof can regulate water runoff on to into lakes and streams while protecting sewer systems from being overwhelmed.
“With climate change, you won’t get the same amount of precipitation but you get it in a shorter duration in bigger, shorter storms,” Taylor said. “If you get water faster than you designed for, then it fills up and it starts backing up and you get flooding. And flooding is very expensive wherever that occurs.”
A blue roof system stores rainwater and slowly releases it using flow-control devices or structures, from customized trays to existing building risers that cause water to dam up. Together, they act as a temporary sponge, collecting and then releasing the water over time.
The stored water also provides the building with a cooling effect through evaporation, as well as additional water for reuse.
On solution to avoid catastrophic climate change is as easy as painting buildings. It’s known that white pain has benefits for cooling cities and on individual buildings it can reduce the use of air conditioning. This has led to a wider adoption of white paint on buildings, and more research into making a more reflective white paint. Prof Xiulin Ruan at Purdue University in the US alongside a team of researchers has created the most reflective white paint ever!
The new paint was revealed in a report in the journal ACS Applied Materials & Interfaces. Three factors are responsible for the paint’s cooling performance. First, barium sulphate was used as the pigment which, unlike conventional titanium dioxide pigment, does not absorb UV light. Second, a high concentration of pigment was used – 60%.
Third, the pigment particles were of varied size. The amount of light scattered by a particle depends on its size, so using a range scatters more of the light spectrum from the sun. Ruan’s lab had assessed more than 100 different materials and tested about 50 formulations for each of the most promising. Their previous whitest paint used calcium carbonate – chalk – and reflected 95.5% sunlight.
This year, Toronto has become the hub for green roofs! Torontist took a look into what made this happen and why green roofs are perfect for cities.
There are approximately 500 green roofs, big and small, in Toronto. This is thanks to a 2010 bylaw [PDF] requiring all new developers to cover between 20 and 60 per cent of their buildings with vegetation. It’s the first (and, for now, only) regulation of its kind in North America, making Toronto uniquely positioned for environmental design.
The bylaw is why the 41-story RBC WaterPark Place [PDF] at Bay Street and Queens Quay has three green roofs that together could fill a NFL football field.
Developers can opt out of installing anything remotely grassy for a fee. But Jane Welsh, City Hall’s project manager for environmental planning, told Torontoist only five per cent of buildings choose to go sans-green roof.
Welsh also says municipally-owned buildings install a green roof anytime there’s a repair or replacement to the top of the building, when feasible.