ACO RoofBloxx being installed at Chalk Farm
September 2021

Blue Roof Solution for Chalk Farm


Two unique semi-detached dwellings have been constructed in Chalk Farm, London featuring an unusual roof design, the roof area covers a total of 46.03 square metres and is divided into six sections comprising two roof lights and three blue roof areas.


Single ply membrane manufacturer RENOLIT ALKORPLAN roofing products and their Approved Roofing contractor Paul Gribben of Gribben Solar Roofing Limited, approached ACO Building Drainage to provide an alternative blue roof solution to the one original proposed.

ACO was asked to provide a practical blue roof solution for the development.


ACO Building Drainage’s in-house technical design team designed an alternative ‘warm roof construction’ blue roof system comprising ACO RoofBloxx units and ACO blue roof flow restrictors.

The ACO team was able to produce hydraulic calculations for its blue roof system which satisfied planning requirements and the needs of the project architects.

The ACO team subsequently provided comprehensive on-site support to assist with and oversee the installation of outlets, flow restrictors and the ACO RoofBloxx units. The system was delivered to site on time and on budget.

Tony Brown, National Technical Manager for RENOLIT ALKORPLAN roofing products, comments: “ACO provided us with a cost-effective, high performance blue roof system and market-leading technical support throughout the project. The system they developed and the technical advice provided were absolutely critical to the success of this project and we are extremely happy with the service provided.”

ACO RoofBloxx is a complete roof attenuation system for blue, green and blue/green roofs. It enables engineers to create a drainage platform that gives architects the design flexibility required to create imaginative, multi-functional open green spaces at roof or podium level.

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