Landscape architecture, garden design, planting design and management - Rowland Byass
Ebbisham Drive green roof

Green roofs offer both wider environmental and localised benefits for the buildings on which they sit. They extend the lifespan of the roof by protecting it from temperature fluctuation, reduce heat gain in summer and heat loss in winter. They are also far more attractive than conventional roofs, particularly in built up urban landscapes.

The existing flat roof was renewed using a bitumastic membrane with Preventol, an anti-root additive to discourage root ingress. Corrugated recycled plastic drainage sheets sit on top of this membrane, separated from the growing medium by porus geotextile fabric.

The plants grow in a free-draining substrate of crushed terracotta and green waste compost, with a small quantity of screened loam to give the medium body and nutrient retention. The substrate is slightly deeper than conventional sedum green roofs, enabling a wider range of plant species to be grown. The roof forms an ongoing experiment into plants suitable for urban green roofs like this one. Since installation, the house is perceptibly cooler on hot summer days. The roof requires almost no maintenance.