UGR Green Roof Root Barrier

Protect your waterproofing from root damage

UGR Green Roof Root Barrier creates a tough physical barrier between your green roof vegetation and the waterproofing layer beneath.

Suitable for extensive and intensive green roof systems, it helps protect the roof structure, waterproofing and services from damage caused by plant and tree roots. It can also provide protection against invasive plants including Japanese knotweed, giant hogweed, bamboo and mares tail.

The membrane is UV stabilised, lightweight to handle and resistant to natural acids, alkalis, bacteria and fungi. Its high puncture resistance makes it suitable for long-term use within both domestic and commercial green roof build-ups.

Triple-coated reinforced construction

Despite being only 0.5mm thick, the root barrier achieves a puncture resistance of 4,500N. Its durable construction consists of:

• Two woven polyethylene reinforcement layers
• A thermoplastic low-density polyethylene coating between the woven layers
• An additional LDPE coating on each external surface
• Thermally bonded layers for added strength and stability

This coating–woven–coating–woven–coating build-up provides strong resistance to puncturing, stress and cracking while remaining easy to cut and install.

Suitable green roof applications

UGR Green Roof Root Barrier can be used as part of:

• Flat green roof systems
• Pitched green roof systems
• Extensive green roofs with lightweight planting
• Intensive green roofs with deeper growing media and larger vegetation
• Domestic roofs, garages, extensions and garden buildings
• Larger commercial green roof projects

Intensive green roofs normally also require a protective fleece above the root barrier to reduce the risk of mechanical damage during installation and ongoing maintenance. See the UGR Green Roof Protection Fleece 300.

Available sizes

Choose from two roll widths:

• 1m x 25m: covers 25m²
• 2m x 25m: covers 50m²

Volume discounts are available when ordering multiple rolls.

Installing the green roof root barrier

Install the root barrier after the primary roof waterproofing has been completed and before laying the green roof drainage and water-storage layers.

1. Roll the membrane out over the waterproofing layer.
2. Cut it to the required length using a sharp pair of scissors.
3. Overlap adjoining sheets by at least 150mm.
4. Seal across the face of each overlap with a compatible 300mm-wide overtape.
5. Where particularly aggressive roots are expected, apply compatible jointing tape between the overlapping sheets before sealing over the joint.
6. Avoid service penetrations through the membrane wherever possible. Any unavoidable penetrations must be carefully sealed using compatible detailing products.
7. Once the root barrier is secure, install the specified green roof drainage layer above it.

Depending on the proposed planting and water-storage requirements, suitable next layers may include the UGR 8mm Deck & Wall Drainage Membrane, or the UGR 20mm, UGR 40mm or UGR 60mm Green Roof Drainage & Storage Membranes and Boards.

Important suitability note

This product is not designed to act as the primary waterproofing or drainage layer. It must be installed over a suitable waterproofing system and beneath a dedicated drainage product such as the UGR 8mm Deck & Wall Drainage Membrane.