When it comes to building sustainable homes, green roofs are one of the more popular options, given both their “green” factor and aesthetical appearance. Not only do green roofs reduce our carbon footprint but are also beneficial not only to our own health, but to those around us.
There are two types of green roofs: Intensive and extensive.
Intensive green roofs are essentially elevated green spaces. Able to sustain shrubs, trees and patio areas.
Extensive green roofs require less maintenance than intensive green roofs and exist more for their environmental benefits as to functioning as a rooftop garden.
Whether intensive or extensive, the layers which form the green roof must accommodate both drainage and waterproofing capabilities.
Waterproofing systems have an incredibly important role to play in the success of a green roof. Not only required to prevent water ingress but to also resist damage to the structure from root penetration.
Not only do waterproofing systems need to be functional as a water proofer but they should also be able to provide the building with thermal performance, roof drainage, air tightness and vapour control. A green roof construction involves a series of functioning layers that, while retaining the necessary water to support the plants/trees/shrubs will also allow excess water to drain off whilst protecting the roof surface from both roots and mechanical damage.
Root barriers are often used in conjunction with waterproofing systems when creating robust green roofs, blue roofs or hybrid roofs.
Root barrier membranes provide protection to the underlaying waterproofing system, often referred to as the primary water proofer. These root barrier membranes protect the waterproofing system from invasive woody roots.
Installing a green roof is relatively straightforward. Once designed, to meet not only building regulations but also client requirements each layer is built into the design. Once a suitable primary waterproofing layer has been installed to the roof deck, this is followed by insulation, a green roof drainage layer, a root barrier followed by a green roof drainage layer. Each membrane layer is supplied in rolls. With lengths of membrane cut to size and abilities to overlap where needed to create a robust solution. Finally, substrates can be added, with an even spread of roof soil across the entire roof area – finally comes the planting of seeds or vegetation layer.
As with any waterproofing system, it’s always important to check the compatibility of the products, using a single source to procure waterproofing systems can offer numerous benefits from warranties to reassurance the products will function as intended.
