Innovative wildflower living roof design helps new motorway services blend in with the surrounding landscape

A brand new £64M service station development has opened at J45 on the M1 in Leeds, located adjacent to Skelton Lake, a 40,000m2 area of ecologically diverse country park 2 miles south east of the city centre.

Living green roof

The design of the building is by local Leeds Architects, Corstorphine + Wright, with a living roof and wildlife centre adding to the natural feel of the building. The main 5,277m2 food court building features the wildflower living roof and is framed by timber eaves to closely echo the surrounding woodland and lakeside habitat, helping to minimise the visual impact of the development. The undulating roof is configured in a unique ‘ribbon’ pattern in eleven separate sections, adjoining a new 100 room Ramada hotel building.

The living roof and wildlife centre adds a natural and unique feel to the building

The green roof plays an important function in the site’s sustainable drainage plan by absorbing rainwater into the roof build up and minimising surface water run-off. The vegetation, growing media and filtration fabrics used within the green roof construction also filter dust and pollution from the air and rainfall, reducing the amount of chemicals and pollutants that reach the surrounding water courses.

As well as contributing to the biodiversity of the development, incorporating a green roof significantly reduces the carbon emissions from the amenity building, allowing the heat generated to be drawn into the cooler roof surface and dissipated more gradually to the environment than with traditional roof constructions.

For the base of the living roof structure, a combination of 20mm and 40mm deep ABG Roofdrain reservoir and drainage geocomposite is installed. The geocomposite includes a geotextile at the top to filter soil particles, and one underneath as a secondary filter and protection layer. The main core structure of the HDPE reservoir board features a matrix of storage cups to attenuate storm water and provide irrigation of the wildflower and sedum planting during dry periods. The geocomposite is supplied in 920mm wide x 50m long rolls, with 110 rolls installed in total at Skelton Lake Services.

ABG Roofdrain reservoir geocomposite being installed onto the water control layer

Extensive wildflower roof build up, incorporating drainage & rainfall attenuation geocomposite layer

Wildflower green roof planting

During the final phase of the green roof construction, a biodiverse growing media mix was deposited directly onto the geocomposite layer and levelled to a depth of 100mm. The material is lightweight to minimise loading on the roof structure and formulated with a high organic content in order to retain moisture and nutrients.

To complete the living roof installation a total of 4,622m2 of meadow planting was installed, in a ratio of 20% grass / 80% flowers including a mixture of 34 different flower species. The turf is supplemented with 14,200m2 of wildflower seed to enhance the density of the meadow and to establish flowering within the wider landscape. An area of 775m2 of sedum planting was also used towards the centre of the facilities building in order to keep the planting below the height of the upper floor RSPB visitor centre with views across the lake.

Growing media and wildflower turf installation

Insulation, water control membrane, green roof layers and irrigation system were installed by Geogreen Solutions and in total 5,000m2 of green roof sedum and wildflower matting, over 6,000m2 of insulation board, geocomposite drainage and waterproof membrane, 28 tonnes of fire break gravel borders and 12 arctic loads of 1m3 growing media bags were delivered and installed for the roof of the new services. Construction started in winter 2018 and completed March 2020.

The green roof system was design by ABG Geosynthetics in conjunction with building architects Corstorphine + Wright, landscape architects Smeeden Foreman and main contractors Morgan Sindall.

For more information and green roof design advice, please contact ABG Geosynthetics on 01484 852096 or email enquiries@abgltd.com

Visitors can enjoy the surrounding walks and look out across Skelton Lake
Green roof install & maintenance carried out by Geogreen Solutions