Background: design and history 

The Grade II* listed Spectrum House was originally designed as the Renault Distribution Centre by Foster Associates (now Foster + Partners). Completed in 1983, the building is characterised by its masted tent roof and bright yellow exposed structure.  

Tom Ravenscroft of Dezeen describes it as “one of the most expressive and distinctive examples” of high-tech architecture. In popular culture, it is perhaps better known as the headquarters of the fictional villain Max Zorin in the 1985 James Bond movie, A View to a Kill.  

Renault sold the building in 2001, and subsequent occupiers have included other distribution businesses and a children’s play centre. 

The roof refurbishment challenge 

By the 2020s, despite a previous overlay and various localised repairs, the roof needed significant refurbishment. With splits and delamination in the single-ply waterproof membrane, it was no longer watertight. 

Project manager MAPP needed a high-performance solution that would preserve the appearance of the listed building. The chosen membrane would need to overlay a variety of substrates while allowing the building to remain operational during the works. 

The key challenge was to create a reliably watertight membrane on a roof featuring a complex geometry, 42 trapezoidal rooflights, numerous penetrations (including 59 masts and their radiating ties) and rooftop plant.  

Water pooling was also an issue. The roof includes a web of valleys that drain into outlet pipes running inside the tubular masts. The existing falls allow water to accumulate but cannot be altered due to the building’s listed status. Therefore, the new membrane would need to be impervious to standing water. 

A durable, seamless solution: Polyroof’s Protec cold liquid-applied roofing system 

MAPP chose Polyroof-approved contractor MLG UK Ltd to carry out the refurbishment using a Polyroof Protec membrane. This offered a number of key benefits: 

Seamless application: Protec forms a continuous, joint-free waterproof membrane – critical for preventing leaks on a roof with such intricate details. 

Versatility: unlike other membranes, a cold liquid-applied membrane can directly overlay a single-ply substrate. Protec can also overlay many other substrates – essential for encapsulating the various penetrations. 

Durability: Protec is impervious to standing water, flexible enough to withstand the natural movement of the building and has a certified 30-year lifespan. 

Safety: the cold liquid-applied membrane ensures the safety of the installers, the building and its occupiers. 

A wide permitted temperature application range: involving such a large roof area, the refurbishment would inevitably span a number of seasons. Used in conjunction with Polyroof’s innovative RapidCure low temperature accelerator and summer inhibitor technologies, Protec can be installed all year round. 

Polyroof’s exceptional service: Polyroof’s technical experts support approved contractors throughout a project – from initial planning and specification to completion of the works. 

The scope and programming of the works 

Most of the roof build up beneath the single-ply membrane was sound. However, an independent survey identified some localised areas of damage caused by water ingress. The roof build up was stripped from these areas and replaced on a like-for-like basis with a complete Protec System including Rockwool insulation.  

The waterproofing works across the whole roof were complex – involving the encapsulation of 236 details. To ensure quality control while minimising disruption to the building’s occupiers, the work was carefully phased ‒ with the roof area divided into 12 zones. 

Safe access routes to rooftop plant were additionally treated with Polyroof’s hard-wearing, anti-slip ProGrip coating, which requires just a single application.  

The Outcome

Due to Protec’s wide permitted temperature application range and ease of application around complex details, this complex 25,000m2 roof refurbishment project took just 10 months to complete. During this time, the building continued to operate with minimal disruption to the occupiers. 

Protec’s durable and seamless finish provides long-lasting waterproofing protection without altering the appearance of the listed building – ensuring its integrity for years to come.