The Beauty of a Green Roof

So we all know that we are in a state of climate crisis and the building sector produces quite a lot of harm to the planet. I had previously covered timber building as a strategy to reduce this impact. If you have not read it yet, here is the link. For this post, we will discuss some sustainable approaches that are designed to combat the energy crisis.

For larger dense cities such as Toronto, the introduction of greenery systems would be beneficial. Now what are these greenery systems that I am talking about; let’s start with the one that you may know, which is the green roofs. Others to be introduced are the green walls, green balconies, indoor sky gardens, and sky gardens. We might get a little technical here but bear with me. These type of infrastructures is a concept that provides environmental friendly functions at the building and urban scales. This post will mainly focus on green roofs.

Green Roof at Downsview Park Station (rendering)

Green Roof

You may have seen green roofs popping up from building to building.

The first benefit of this system is that it reduces stormwater runoff – the main cause of that stream of water on the street decreasing visibility in urban areas. To reduce that will improve the quality of the street.

Another perk about the wonderful green roof is creating another green space, which in turn creates a habitat for wildlife. It also provides more oxygen and removing carbon dioxide. I like the sounds of that, don’t you?

More Perks of this System

ALSO! It will save some money on energy!! Studies of green roofs have been conducted in Canada and the results showed that the use of green roofs reduce heat gain by 70-90% in the summer and prevents heat loss by 10-30% in the winter.

Reduce heat gain by 70-90%… prevents heat loss by 10-30%

If you go with the installation, it will increase your property’s value. Win-win situation, reducing your demand in heating and cooling systems and increasing your property’s value; sounds pretty good to me!

Recreational opportunities can come from this as well. Green roofs would increase rooftop activities. These green roofs can provide a space for the community to interact. Creating space for people to plant different vegetation – an urban farm. When living in a highly dense city, there are a LOT of noises and with green roofs, they reduce that noise pollution. Great way to reduce annoying traffic sounds! The more vegetation the better, because it will also result in the improvement of air quality.

Now there are a few different types of green roofs but to keep it short, for human use an intensive green roof is required. A lot of these systems are a great solution for new buildings as well as older buildings. Another type is the extensive green roof and these are favorable for those older, poorly insulated buildings. The green roof also acts as another layer of insulation whatever type it is. This is due to the main function of the green roof that is to prevent solar radiation. This greenery system is a passive cooling technique that prevents solar radiation from coming into contact with the building’s structure. I said this previously but with the installation of a green roof, the demand for heating and cooling systems are reduced… meaning less carbon dioxide. It also depends on the plants chosen to sequester carbon dioxide from the air and store it as biomass.


I am not going to go in depth of the layers required but the main layers of an intensive green roof begin with the roofing membrane, waterproofing layer, root barrier, protection mat, drainage later, filter sheet, growing substrate, and finally the vegetation. There are also some factors that come with this type of green roof such as, the depth and composition of growing media, climates, plants, and type of irrigation and insulation specifications.

For further explanation on these layers:

Buildings with green roofs in Toronto

Within highly dense cities, such as Toronto, there is something called the heat island effect. It occurs in urban areas due to the increase of humans, which alters the temperature. By retrofitting buildings for green roofs, it will be talking that heat island effect.

A few buildings within Toronto can be found at:

Ryerson’s Urban Farm

Ryerson Urban Farm on the roof at 245 Church Street, Toronto, Ontario

York University’s Lassonde building

Sherway Gardens Shopping Centre

To find more information on building green roofs in Toronto:

Time to Green that Roof

As you can tell, there are many benefits of green roofs. With the installation of this system, it brings greenery to a very grey city as well as tackling climate issues. So if you are looking for another project challenge yourself with a green roof.