ΞΆΓάΘ¦

Read our policy.

A - Indicative thicknesses for roof layers
Type Thickness* Dead load** Rainfall retention
Extensive 50 mm 0.7 kN/mΒ² 50%+
Semi-extensive 200 mm 5 kN/mΒ² 70%+
Intensive 600 mm 10 kN/mΒ² n/a
* Overall thickness for growing medium and drainage layer
** Dead load based on fully saturated soil and drainage layer
B - Indicative costs of green roof
Sedum blanket onlyΒ£35–40/³ΎΒ²
Sedum blanket with drainage layer and filter fleeceΒ£45–65/³ΎΒ²
Sedum blanket on filter fleece and drainage layers, capping layer and vapour barrierΒ£80-115/³ΎΒ²
Extra for insulationΒ£50/³ΎΒ²
Extra for waterproof membrane and vapour barrierΒ£30-45/³ΎΒ²
250 mm thick growing medium on drainage board, root membranes and insulation; turfΒ£85–100/³ΎΒ²
225 mm thick growing medium on filter fleece and LDPE drainage core; plug and hydroseed plantingΒ£50–60/³ΎΒ²