BREEAM excellent rating for BFI Master Film Store


• Project: BFI Master Film Store
• Scope of project: Bespoke waterproofing to building envelope with feature green roof
• Year completed: 2009
• Products used:
Flagon TPO EP/PR 1.5 Sand Grey Membrane
Extensive Green Roof System
SOPREMA EPS insulation


The BFI Master Film Store is considered one of the most important buildings for the preservation of British film. The challenge that Edward Cullinan Architects had was that the material to be stored in the building is the BFI’s National Collection of Film masters. Much of the pre 1950’s film, is a nitrate based material which is highly flammable that could burst into flames, if not stored at the correct and stable temperature. If any of these films become damaged the images are lost forever.

A new building was required to store the 450,000 cans of film. A detailed specification was created for the project, that was essentially to be a cold dry fridge which keeps the film at -5 degrees and 35% relative humidity. The building itself is incredibly ecologically sustainable and consists of a series of fire proof cells, many preventatives installed and designed to vent fire and fumes, but also to prevent fire spreading along the series of cells.

The roof was an incredibly important factor in the success of this project. The Single Ply Flag Sand Grey TPO EP/PR membrane was a major part of the airtight system that the architects had specified, incorporating an RIW sheet seal membrane into the waterproofing system. The green roof was specified to ensure the environmental impact of the new building was kept to an absolute minimum, and replace the original footprint of the building.


Each part of the structure has been carefully designed and products selected, adapted and installed using innovative methods and bespoke detailing. The historical value of the films stored in this building is of the upmost importance to the history and culture of this country and others, and so the detail and innovation applied to this project reflects this importance. Flag TPO waterproofing membrane is renowned for its flexibility and resistance to extreme temperature changes, the waterproofing was completed to an extremely high standard meaning that the air tightness and humidity levels of the building will be easily maintained, and the building envelope could withstand structural movement due to temperature changes.


Sustainability and the environment were major drivers of this project, which has been built on a nuclear bunker site in the countryside. The store is highly insulated (0.1W/m2K) and air tight (0.3m3/hr@50pa) in order to sustain a BREEAM excellent rating, setting a benchmark for the preservation of film world wide. The RIW sheetseal system had to be incorporated into the single ply waterproofing system to encapsulate the building envelope. The system’s light weight and guarantee of performance for 25 years offered clear performance benefits in keeping with the client’s requirements for demonstratable sustainability.