A Guide to Green Roofs

INTEGRATING green roofs into building designs requires careful planning and consideration to ensure both functionality and sustainability.

The first crucial step is to identify the specification requirements and, for optimum results, it’s worth partnering with an expert supplier like SOPREMA early on in the design stage for blue as well as green roof specifications.

Types of Green Roofs

Once the initial requirements are agreed upon, the type of roof construction can be specified. For example, extensive green roofs are lightweight, featuring shallow soil depths 5-15cm (2-6 inches). They support low-maintenance vegetation like mosses, sedums, and grasses, making them ideal for buildings with limited load-bearing capacity. Plus, they require minimal maintenance.

Alternatively, intensive green roofs resemble traditional gardens, featuring deeper soil layers that can reach up to several feet. This allows them to support a diverse range of plants, including shrubs and trees. While they require robust structural support and ongoing maintenance, they provide significant aesthetic and recreational benefits.

Finally, semi-intensive green roofs combine elements of both extensive and intensive green roofs, with moderate soil depths and a mix of plant types. They provide a balance between weight, maintenance, and biodiversity.

Structural Reinforcements

If more substantial vegetation like bushes and trees need to be planted, the existing structure’s ability to support the added weight of the green roof system, including saturated soil, plants, and any additional features like irrigation systems or walkways, needs to be assessed.

When considering a green roof, structural reinforcements or modifications are often necessary. This could mean strengthening beams, columns, and the roof deck to support any additional weight. It’s crucial to account for the green roof’s weight at full saturation point, and not only dry vegetation.

Waterproofing and Drainage

Effective waterproofing and drainage are vital to prevent water infiltration and potential damage. High-quality waterproof membranes and drainage layers are essential to protect the roof structure and facilitate proper water flow, preventing waterlogging. These membranes must be durable and resistant to root penetration to avoid future structural issues.

For precise product specifications related to root water and drainage protection, our technical experts at SOPREMA can guide you with advice and calculations where necessary.

SOPREMA can also advise on a wide range of waterproofing options that are sufficiently root-resistant. These include reinforced bitumen systems, liquid systems, and structural waterproofing. Among the most robust choices for root-resistant capsheets in multi-layer waterproofing systems is SOPRALENE FLAM GARDEN 250 AF.

By addressing these elements and partnering with an industry expert like SOPREMA, architects can create resilient, sustainable buildings.

If your next project is a green roof, get in touch with SOPREMA’s technical experts here.

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