M-Tray® – Turing House school project

Wildflower and PV panel project for new school build

Turing House represented one of the largest modular green roof projects Wallbarn has supplied.

This new build school in South West London required a green roof of over 1,500m². Many of the roofs M-Tray® covers have hitherto been domestic, small scale commercial and retrofit green roofs. To work on such a large new build was an exciting challenge for Wallbarn.

Wallbarn worked closely with the developer of the school project Bowmer & Kirkland and their appointed landscaping contractor Kingston Landscapes.

The roof space was on a number of different levels with services, wiring and ducts throughout with walkways and angled parapets.

The intention was to provide a natural protective covering for the single ply waterproofing membrane and introduce a number of environmental benefits to the new build.

BREAAM points were taken into consideration and the client wanted an area that could potentially prove an educational focus for the pupils once the building was occupied.

They required a green roof that was established and healthy which was able to be installed quickly and easily as deadlines were extremely tight. M-Tray® wildflower was the perfect product.

Delivery was easy and efficient due to the nature of the modular wildflower product. Modules were stacked onto pallets and delivered in an articulated vehicle for fast offloading and stacking.

The heavy duty forklift on site was able to lay all pallets out into position ready for lifting onto the roof.

A largescale cherry picker hoist was employed to lift the pallets onto the roof.

Each full articulated load of > 600m² easily lifted onto the roof space within a couple of hours.

Not only did this mean that installation was able to be carried out quickly, the length of time that the sedum & wildflower plants were stacked up was significantly reduced which meant healthier plants and a more established, instant green roof.

The cherry picker dropped each pallet onto a trolley which was pushed to the relevant section of the roof space. Installation was thus immediate.

The trays are designed with a series of clips and notches in the walls of the modules, so that each module is clicked together creating a seamless green roof space also immediately.

The modules have a base planting scheme of sedum varieties to give a ground cover of all year round vegetation. There is also a large selection of native wildflowers and herbs and even in November, when this project was installed, flowers were still present and bees and butterflies were still being drawn to the roof.

Sections of this roof were devoted to photovoltaic panels to help generate heat and electricity for the school.

It was possible to lay the 500 x 500mm modules between each PV panel to increase the sustainability of the roof and by extension, the school building in its entirety.

Modular green roof systems are ideal to use with PV panels as they can be lifted easily to inspect either the wiring or services of the panels or if any of the panel themselves ever need to be replace in the future.

The contrast with a roll-out roof where the substrate and drainage membranes would need to be dug out is obvious.

Over the winter of 2021 and leading into the spring of 2022 the green roof matured and established itself. The plants flowered and grew up to form a seamless green roof.

The area is lush and beautiful and a haven for wildlife. The contrast with a grey, bare single ply roof space across such a large area is vast. What could have been an ugly surface which would heat up in summer and leave the waterproofing membrane exposed to elements in the long term has become a protected, insulated, natural space in the sky.

The school is due to open in the autumn of 2022 and both the head teacher at the school, the landscape contractor and Bowmer & Kirkland, the developer of the whole school project, have all stated how pleased they are with the roof.

We await the feedback from the pupils once they arrive at their new school.