UGR 40mm Storage & Drainage Board 1m x 2m

High-capacity drainage and water storage

UGR 40mm Storage & Drainage Board is a heavy-duty water-management layer designed primarily for intensive green roofs and hard landscaping applications.

Its deep 40mm cavities retain around 15 litres of water per square metre, helping maintain moisture around the growing substrate and vegetation between periods of rainfall. Perforations within the membrane allow excess water to drain away, reducing the risk of the planting layers becoming saturated.

The combination of high water storage and strong drainage performance makes UGR 40mm Storage & Drainage Boards particularly useful for heavily planted roofs, long drainage runs and roofs with a low gradient.

Built for intensive planting and heavier loads

Manufactured from 100% recycled high-density polyethylene, UGR 40mm Storage & Drainage Board has an approximate compressive strength of 200kN/m² — equivalent to around 20 tonnes per square metre. This makes it suitable for a wide variety of soft and hard landscaping applications, including:

• Intensive green roofs
• Roof gardens
• Wildflower, plug and seed planting
• Grass, shrubs and medium-sized planting
• Commercial and residential roofs
• Inverted warm roofs and cold roofs
• Balconies and terraces
• Landscaped areas above underground car parks
• Ground-level landscaping above basement accommodation
• Walkable decks
• Drivable decks
• Paving and slab build-ups

Its drainage capacity also allows it to accommodate large drainage lengths or low roof slopes within a correctly designed system.

Water storage for demanding planting schemes

Intensive green roofs generally use deeper growing substrates and support larger, more varied vegetation than lightweight extensive systems. UGR 40mm Storage & Drainage Boards help manage water within these deeper build-ups by:

• Retaining useful rainfall within its 40mm cavities
• Allowing excess water to pass into the drainage space
• Supporting heavily planted areas during drier periods
• Providing approximately 3.78l/(s·m) drainage capacity at a hydraulic gradient of 0.10
• Withstanding substantial loads from substrate, planting and compatible hard landscaping

A separate geotextile filter layer is required above UGR 40mm Boards when they are used beneath planting substrate. This stops soil and fine particles from entering and obstructing the storage cavities. Use the UGR 120g Green Roof Filter Layer.

Where UGR 40mm Storage & Drainage Boards fit in the system

A typical intensive green roof build-up may include:

1. Structural roof deck
2. Primary waterproofing layer
3. Root barrier
4. Protection fleece
5. UGR 40mm Storage & Drainage Board 1m x 2m
6. Separate geotextile filter layer
7. Intensive green roof substrate
8. Planting or turf

For dedicated root protection, install the UGR Green Roof Root Barrier beneath the drainage membrane. A protection fleece may also be required to reduce the risk of light mechanical damage to the waterproofing and root barrier — see the UGR Green Roof Protection Fleece 300.

Installing UGR 40mm Boards

The application surface should have a gradient of at least 2%. Complete the horizontal waterproofing, root barrier and any other specified underlying layers before installing the slabs.

1. Lay the 1m x 2m slabs horizontally with the cavity openings facing upwards.
2. Position adjoining slabs edge to edge using butt joints; overlapping is not normally required.
3. Cut slabs to fit using a suitable knife, taking care not to damage the waterproofing or other layers beneath.
4. Where additional protection is required at a joint, a compatible single-sided membrane tape may be applied over the connection.
5. For planted areas, install UGR 120g Green Roof Filter Layer over the completed surface.
6. Apply the specified intensive green roof substrate over the filter layer.
7. Complete the system with the selected vegetation.

The manageable slab size allows individual sections to be positioned and cut without handling a large roll.

Walkable and drivable applications

For walkable areas without vegetation, a geotextile filter layer is not used. The specified base and bedding materials are instead applied directly onto the membrane and into the cavities before the paving or slabs are installed.

Drivable applications require a suitable sub-base and bedding course between UGR 40mm Storage & Drainage Board and the finished pavement. The complete build-up, loading and drainage design must be appropriately specified for the intended use.

Durable and long-lasting

UGR 40mm Storage & Drainage Board is:

• Made from 100% recycled HDPE
• Highly resistant to water
• Resistant to alkalis and saline solutions
• Resistant to organic acids
• Resistant to bacteria, fungi and other small organisms
• Unaffected by minerals
• Suitable for temperatures between -30°C and +80°C
• Guaranteed against deterioration for 30 years
• Tested and CE marked to the relevant standard

Its stated life expectancy is equal to that of the structure under DIN 9001:2000.

Important suitability note

UGR 40mm Storage & Drainage Board is a deep, heavy-duty drainage layer intended mainly for intensive planting and compatible hard landscaping. For a lighter extensive green roof that does not require this level of water storage or load resistance, consider the UGR 20mm Storage & Drainage Membrane 2m x 10m.

UGR 40mm Board is not a primary waterproofing membrane and must be installed above a suitable waterproofing system.