Planted roof systems
Wallbarn produces an extensive green roof system in a modular format, called M-TRAY.
M-TRAY is a ready-grown, fully established sedum, sedum-and-wildflower or wildflower-only green roof loaded into a portable tray, for easier installation of green roofs.
All the growing, filtration and drainage elements are included in the system and the shape of the modules means that each one is simply laid onto the deck and clipped to the next module to create one seamless, fully established green roof.
The major benefit of M-TRAY is flexibility. Getting it to the roof is not a disruptive and costly process, which is a huge advantage over loose lay systems. It is simply not possible to loose lay roll-out systems layer-by-layer on some roof areas due to access restrictions. M-TRAY can reach the roofs other systems cannot reach.
Access to the roof is future-proofed. If there are problems with the deck beneath or inspection is required, one M-TRAY or section can easily be lifted out without any disruption to the whole deck. With loose lay systems, the whole area may need to be destroyed when accessing the deck.
It is ideal as a temporary green roof system. Each M-TRAY is 540mm x 540mm x 90mm deep. The edge has lugs which can be clipped into the lug of the next tray or unit. The sedum grows above this level to help hide the joints. This interlocking system means that each M-TRAY is fitted securely to its neighbour with no need for sharp fixings going through the waterproofing beneath. The sedum growth is not restricted and can mingle across the whole area.
The M-TRAY modules are pre-grown in Wallbarns UK nursery. The empty modules are made from polypropylene and are manufactured with an angled base which creates a large surface area for the roots to establish. The module is lined with a geotextile filter fabric and then filled with the aggregate substrate mix. The exact makeup of the mix depends on what type of plants the growers are propagating in that particular batch.
The vegetation is then planted into the substrate, either from cuttings or seeds (cuttings illustrated above). We use a mix of different species of sedum designed to ensure all-year growth, some flowers and variation throughout the summer, durability and ability to be resistant to periods without rainfall.
The vegetation is grown onto the M-TRAYS for a minimum six months to ensure strong, well established, healthy plants, fully integrated into the intermediate layers with solid root structures. This means less shock or bedding-in time and less risk of wind uplift or erosion in the crucial time period after installation.