CommercialOne Central Boulevard
Solihull, West MidlandsSingle Ply
06Waterproofing system
Green Roofing
A green roof is a waterproofing project with planting on top. Absolute Waterproofing installs extensive sedum, biodiverse and intensive systems complete with the root barrier, drainage, filtration and growing medium, over a structural membrane specified to outlast the vegetation above it.
- System types
- Extensive, biodiverse and intensive
- Saturated load
- From around 80 kg/m² extensive
- Root resistance
- FLL tested barrier as standard
- Maintenance
- Planned visits, typically twice yearly
About Green Roofing
Green roofs are increasingly written into planning conditions, biodiversity net gain requirements and BREEAM targets. The risk is that the vegetation gets the attention and the waterproofing beneath it does not, which is the wrong way round. Everything above the membrane can be replaced. The membrane cannot.
We build green roofs from the deck up as a single waterproofing package: structural membrane, root barrier tested to FLL, drainage and reservoir layer, filter fleece, substrate and vegetation. One contractor, one guarantee, no interface between trades where responsibility can be lost.
Extensive sedum systems suit most commercial applications, need little maintenance and add modest load. Biodiverse systems built from varied substrate depths deliver far more ecological value where planning requires it. Intensive roof gardens are possible where the structure has been designed for the load.
Best suited to
- Planning conditions and biodiversity net gain
- BREEAM and sustainability targets
- Attenuating rainwater discharge
- Overlooked roofs where appearance matters
Sectors we install it in
Typical build-up
Section / outside in- 01
Vegetation
Sedum blanket, plug planting or biodiverse seeding
- 02
Growing medium
Engineered substrate, depth set by system type
- 03
Filter fleece
Retains substrate, passes water
- 04
Drainage and reservoir
Holds water for the plants, drains the excess
- 05
Root barrier
Root resistant to FLL test standard
- 06
Waterproofing membrane
Usually hot melt or a root-resistant bituminous system
Specifying this system?
We issue technical submittals, U-value calculations, wind uplift calculations and detail drawings as part of the tender return.
Send us the specificationDelivered
All case studiesProjects using this system
Common questions
Green Roofing, answered
Will our structure take a green roof?
An extensive sedum system adds roughly 80 to 120 kg/m² saturated. That is within the capacity of most concrete decks but needs checking on lightweight metal. We will flag it early and can arrange a structural appraisal before you commit.
What maintenance does a green roof need?
Extensive systems need two visits a year: weeding out invasive species, clearing outlets and vegetation-free zones, and feeding. We include green roof maintenance within our planned maintenance agreements.
Tender & project enquiries
Have a project for us?
Send Absolute Waterproofing your roofing enquiry or tender. Drawings, specifications and a link to the tender information can all go with it, and our estimating team will come back to you with a considered price rather than a holding email.
