Why green roofs will continue to boom in the future
June 2023
Green roofs are booming. Not only do they provide a wealth of environmental and economic benefits, they also provide major opportunities for contractors. According to a recent report by the Green Roof Organisation (GRO), the Green Roof market in the UK continues to expand significantly, having risen from around 1.17 million square metres in 2015, to 2.15 million square metres by 2019, with the potential of a further 20% growth by 2025.
The figures tell the story. Green roofs offer roofing contractors massive potential, with the market expected to expand within the next two years to some 300 million square metres.
It is likely there will be a particular need for contractors who are experienced in installing and maintaining green roofs, with the bonus that such specialists should be able to earn better margins due to the highly skilled nature of the work.
With increasing concerns about climate change, green roofs, also known as living roofs, are becoming more popular in the UK due to their numerous environmental and economic benefits. A green roof is described as one that is partially or completely covered with vegetation, typically planted over a waterproofing membrane, and is designed to absorb rainwater, reduce urban heat island effects, provide insulation, and create new habitats for wildlife.
In addition to environmental benefits, green roofs also provide economic advantages. It’s known, for example, that green roofs can increase the lifespan of the roof membrane by protecting it from UV rays and extreme temperatures. They can also reduce the need for heating and cooling, which can lead to lower energy bills – and for home owners - green roofs can increase the value of a property, making it more attractive to potential buyers or tenants.
When installing a green roof, choosing the right waterproof membrane is critical to ensure the longevity and effectiveness of the roof. At Proteus we work closely with our approved contractors who are trained to install our Pro-Living® roofs using any one of a number of different membranes.
A typical case study was one recently undertaken with approved installers Millane Contract Services Ltd at Porteus Place in Clapham which used our highly versatile Pro-BW® membrane.
Located in the heart of Clapham Old Town, Porteus Place is a contemporary purpose-built development that runs off Clapham Common North Side.
The existing hot melt roof covering at Porteus Place was failing causing water ingress into the luxury apartments below and huge disruption to its residents. As well as the failed waterproofing, the existing 500 sq metre green roof had deteriorated beyond repair from poor maintenance, and in turn, had begun to solidify meaning it was no longer complying with fire regulations.
The client specifically requested a long-lasting waterproofing that was BRoofT4 certified, and a new green roof that complied to the GRO Green Roof Code of Practice. Alongside Proteus Waterproofing, Millane Contract Services Ltd, were able to provide the client with the complete reassurance of a safe, fully compliant green roof, as well as a long term, robust Pro-BW® Plus waterproofing system.
Replacing the existing waterproofing and green roof presented enormous challenges, particularly in the early stages of the project. All existing roof finishes including timber decking, slabs, EPS insulation and ballast were manually removed to expose the existing hot melt waterproofing. Due to high levels of water saturation, it took three men to physically remove each individual insulation board, making this an incredibly time-consuming process. These surfaces were then jet washed and prepared ready to receive the new Pro-BW® Plus waterproofing.
Following the removal of the existing glass panelling to the balustrade and perimeter, Pro-BW® Plus was extended onto the 300 metal pitch pockets installed around the balustrade support, providing a continuous, seamless waterproofing protection guaranteed for 25 years.
To enable the green roof on the main roof area to retain and slowly release water, a drainage layer was installed, followed by a filter fleece and an extensive substrate. This allowed for the installation of a sedum blanket.
Telescopic drainage trims were then installed to the perimeter of the green roof. Cobbles were laid around the perimeter and fire breaks to eliminate the spread of flame across the roof area in the event of a fire. All existing glass panels could then be reinstated onto the balustrade post.
An irrigation system, which wasn’t present with the original green roof, was introduced. This required the installation of a water pump to ensure the correct water pressure was available to maintain the roof.
Pro-BW® Plus was the perfect waterproofing solution for this complex project as it is BBA green roof certified. It can be used in an inverted and green roof scenario with flat and zero fall properties. It is liquid applied providing ease of application to all roof areas, including the numerous glass balustrade supporting details.
Collaboratively, Proteus Waterproofing Ltd and Millane Contract Services Ltd successfully delivered this project to an impeccable standard resulting in one incredibly satisfied client, and another fully protected, environmentally friendly, watertight project.
While this project offered many challenges, it is clear that this is the type of contract that is now becoming more and more common. The green roof market in the UK is growing and choosing the right waterproof membrane, installed by skilled contractors, is critical for the longevity and effectiveness of such a roof.
At Proteus, we believe this is just the beginning, and we are ready.