Case Study - Shaw’s Cottage, London Borough of Lewisham
Client
Architect
Main Contractor
Type of Development
Two-storey timber framed private house built using the Segal method.
Reason for Green Roof
Biodiversity
Footprint replacement
Type of Roof
Extensive
Size of Green Roof
approx. 100m2
Build up of Roof
Single ply butyl membrane covered by protective fleece. 60mm of rubble and subsoil covered by turf and on the pitch, gravel. On the steeper slopes a timber framework was constructed on top of the fleece to stabilize the substrate and a biodegradable jute covering mat used to prevent erosion during establishment. Gravel filled gutters connected to downpipes
Details of Green Roof Element
Designed to provide a variety of substrates and aspects, with areas of gravel/soil on flat areas, and chalk rubble/garden soil on pitched sections. The roof was partly turfed with lawn grass from the site and partly left to colonise naturally
Comments
By 2001 the vegetation of the different areas had become similar, despite the differing soil chemistry and aspects. Turfed areas were found to support a dense tussocky grassland sward comprising species such as Agrostis stolonifera, Dactylis glomerata and Phleum bertolonii, with herbs including Cerastium fontanum, Trifolium repens, Plantago lanceolata, Rumex obtusifolius, Malvasylvestris and, in disturbed areas, Medicago lupulina and Euphorbia peplus. Sedum had colonised the gravel.
The roof was designed by EcoSchemes Ltd in consultation with the owner and architect John Broome in 1993.