EDITORS CHOICE
LIVING ROOFS, LASTING IMPACT:
HOW IRRIGATION SUPPORTS SUSTAINABLE GREEN ROOF DESIGN FOR EVERY APPLICATION
Green Roof Terrace Central London
The Rise of Green Roofs in Urban Design Green roofs are an increasingly common feature if not an essential part of the urban landscape, delivering benefits that range from biodiversity gains to improved thermal performance. These systems fall into two broad categories: extensive roofs, typically lowmaintenance and intended for ecological value, and intensive green roofs which are deeper, landscaped environments, often designed for human use.
Design Complexity and Irrigation Needs Projects like the landmark new development in King’ s Cross are showcasing just how multifunctional these spaces can be. However, their long-term success depends on more than just the planting selection. Irrigation plays a vital role, particularly where deeper substrates and diverse species require consistent moisture to establish and thrive.
When Irrigation Is Essential At Waterscapes, we work closely with design teams to determine whether irrigation is necessary, and if so, the most effective way to integrate it. As a general rule, intensive green roofs should always be irrigated, as should any roof designed for seasonal colour, pollinator planting, or public access. Even extensive roofs can benefit from irrigation during periods of prolonged drought, to maintain biodiversity and reduce fire risk.
System Design and Sustainability Integration We deploy both surface and subsurface dripline systems, depending on planting schemes, substrate depths and maintenance access. Systems are pressure-compensated and typically paired with smart controllers to optimise water use. Where feasible, a green roof should incorporate rainwater harvesting or SuDS integration— aligning with sustainability targets and reducing reliance on potable water.
Fire Resilience and Climate Adaptation Fire resilience is becoming a more prominent consideration, particularly in dense urban zones where dry rooftop vegetation could pose a risk. Correctly designed irrigation significantly reduces this threat, ensuring green roofs remain safe and compliant while supporting biodiversity throughout the seasons.
GRO Code and Best Practice Compliance It’ s essential to refer to the GRO( Green Roof Code), which provides comprehensive industry guidance on the design, installation, and maintenance of green roofs. This includes critical detail on substrate depths, fire performance classifications, biodiversity requirements, and the need for adequate irrigation in intensive systems. Adhering to the GRO
Code not only ensures compliance with current best practice but also future-proofs green roofs against environmental stressors and evolving regulatory expectations.
An Ecological Investment, Not an Optional Extra With urban environments under pressure to deliver both green and blue infrastructure, green roofs offer a rare dual benefit; softening hardscapes while contributing to drainage and climate adaptation. But they are not maintenance-free. Irrigation isn’ t optional on these projects it’ s an ecological safeguard and a fire prevention strategy.
If you would like to know more about these projects or others that
Waterscapes have been involved with contact us.
Web: waterscapes. co. uk Email: info @ waterscapes. co. uk;
Follow Us: @ waterscapesltd
Dripline on Extensive Green Roof Prior to Planting
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