Green roofs

Edge Trim

Our Aluminium Edge Trim is versatile and can be used in various ways depending on the green roof system you are installing. It enhances the exterior aesthetic of any system and is essential for containing pebble borders when there is no parapet or raised upstand.

In rollout systems, it effectively separates vegetation from areas like pebble borders, drains, and roof lights. The trim’s right-angled aluminium profile fits neatly against the deck, allowing it to sit underneath and be secured by the weight of either the M-Trays® or additional pebbles.

Pebbles

Building regulations and the GRO Code require the installation of a pebble border around the perimeter of a green roof and around features such as roof lights and drainage outlets to act as a fire break.

We recommend using clean, rounded river stone pebbles that are free from foreign materials and dirt. Wallbarn supplies these pebbles in large 1-tonne bulk bags or more manageable 25kg single bags, facilitating easy transportation to the roof.

Our technical team is on hand to provide advice and estimate the quantity needed for your project.

Geotextile

We offer a diverse selection of geotextile fabrics suitable for filtration, separation, and protection purposes for any type of green roof. A geotextile is the first layer applied to any green roof, providing protection for the roofing membrane while filtering small particles and allowing moisture to pass through. It is also used above the drainage board as a filtration layer in rollout green roof systems.

Our recommended options to ensure you meet GRO Code specifications are:

• Recycled Polypropylene PPT 400 GSM
• Recycled Polypropylene PPT 500 GSM
• High Tenacity Virgin Polypropylene PPST 150 GSM

These geotextiles exceed the tensile strength and puncture resistance requirements outlined in the GRO Code. As the least expensive component of any green roof, it is advisable to ensure it meets specification.

Fertiliser

Sedum green roofs are notably resilient, and most all-purpose fertilisers are suitable for their upkeep. However, we highly recommend the Vitax Q4 natural and organic fertiliser, available from Wallbarn.

This all-purpose fertiliser is enriched with mycorrhizal fungi, helpful bacteria, and biostimulants, all of which significantly enhance rapid root growth and establishment.

Inspection Box

The JacBox (inspection box) is crafted from powder-coated aluminium, ensuring corrosion resistance and offering a range of colour options.

It is readily available and in stock with a black powder-coated finish, and comes with bases either 50mm or 300mm high in a full-slot design, suitable for standard or parapet applications. The slots are designed to allow the free flow of rainwater.

With various extension components, you can achieve any required depth of roofing buildup. Interlocking mid-sections are available in four different sizes, enabling multiple build-up heights. These sections are lightweight, easy to assemble, and quick to install.

The boxes can be powder-coated to match any RAL colour required. Additionally, the lid is lockable to enhance security.

Gravel Excluders

Our gravel excluders, available in plastic, are designed for use in circular drain connectors and roof outlets where the area is covered with a gravel or pebble layer, such as border edges or shingle ballast in an inverted roof system.

Constructed from polypropylene, these excluders feature a sturdy cage on the top, strong sidebars, and slats to allow water to drain through.

We offer two main designs: the Helix spoke, which includes three wide spokes, and the Spider fitting, featuring an angled four-spoke design. Both designs enable installers to easily trim the spokes with a sharp knife to fit the diameter of the outlet holes perfectly.

The Sombra gravel excluder is an ideal cover for outlets with a diameter of up to 180mm and is particularly suitable for use on green roofs, accommodating pebble heights up to 150mm.