Green roofs in our daily lives are becoming more and more commonplace. Developers, architects, and even residential homeowners are searching for ways to improve their carbon footprint and provide sustainable (and beautiful) building solutions; green roofs are one of the best ways to do that.
That being said, there are some serious pros and cons to consider about green roofs. Let’s take a look.
Green Roofs: Defining and Understanding How they Work
Simply put: a green roof refers to any roof that intentionally includes vegetation – meaning, sadly, that the moss growing between your shingles doesn’t count!
A green roof can be as simple as a grass roof or as complex as large, physically deep installations featuring trees, gardens, and pathways that look more like a park than a roof. And, while they can be beautiful and functional, there’s a lot to consider before you go that route.
The Pros and Cons of Green Roofs
Believe it or not, green roofs have been around for thousands of years – in one form or another. Research suggests that the practice of growing trees atop buildings dates back to ancient Rome. Sod roofs date back to the middle ages in Scandinavia.
Now, green roofs are becoming more and more common in urban spaces across the world because they offer many environmental, social, aesthetic, and even financial benefits. But are they more beneficial than other kinds of roofs? This blog aims to explain the unique benefits of green roofs while also breaking down the main categories one can choose to install.
Let’s start with the pros.
Pros
Green roofs look great. There are many, many ways to customize your roof, from simple, low growing plants to entire park systems, including full sized plants and even trees. You’ll see these on many apartment buildings in Vancouver, including the library and the courthouse [links].
Green roofs offer great insulation. Even a simple, shallow green roof offers excellent insulating properties, meaning your heating and cooling bills are likely to be lower.
Green roofs are environmentally friendly. They can reduce air pollution, improve air quality, provide natural stormwater management and remediation, cool cities, and improve biodiversity.
Green roofs are socially beneficially. When a green roof is like a park, it can provide a green space for recreation, which helps promote physical activity and social interactions.
Green roofs can increase property value. They improve cub appeal and positively influence the perception of potential buyers.
Cons
All that said, there are certainly some drawbacks to green roofs as well. Let’s take a look.
Green roofs are made of plants, and plants are high maintenance. Even a small sod, sedum, or pollinator green roof requires a great deal of maintenance. If your green roof includes an entire park system, it requires even more. That means hiring a qualified company to take care of the plants, drainage, and membranes.
Green roofs are still roofs, and roofs need all the usual maintenance, too. If you have three feet of soil, grass, plants, and trees on top of your membrane, it’s going to be subject to a lot of wear and tear. Roots from the trees can disrupt membranes and drains, for example, causing massive problems that will cause thousands and thousands of dollars to fix because you’ll have to dig everything up in order to repair any issues, then put it all back when you’re done. This requires the coordination of many different contractors over an extended timeline.
Green roofs are expensive. Installation, maintenance, repairs, landscaping – the list goes on. The larger the green roof, the more costly it is,
What’s left to consider?
Just ask yourself if the benefits outweigh the costs. Green roofs offer many, many benefits – socially, environmentally, and aesthetically, but they also have plenty of drawbacks.
It’s also worth checking local bylaws and guidelines. Many cities, including Vancouver, have begun to mandate green roof installations for buildings of a certain type and size. It’s easy to see why by the environmental benefits alone, but, like most things, a lot of research is needed if you want to decide for yourself!
Got any questions?
To be clear: at Cambie Roofing, we do not install green roofs. However, we can certainly help with membrane repairs and inspections wheen needed. Get in touch with us for more information – we’d love to hear from you!