British Gas Stockport
WestWood partnered with specialist contractors, Everlast Group, to strip back and refurbish a 5,000m2 metal roof
Key Statistics
British Gas Stockport Waterproofing Case Study
WestWood partnered with specialist contractors, Everlast Group, to strip back and refurbish a 5,000
sq. m metal roof, delivering a waterproofing system while the building remained operational.
Comprising office space for up to 600 people and an events area, this building is a regional hub for British Gas. Its 5,000 sq. m metal roof was leaking, requiring a full refurbishment without disrupting the offices below.
WestWood’s Weproof 264 waterproofing system was selected for the project, incorporating a low-odour, quick-curing PMMA liquid-applied membrane.
Solvent-free, the resin can cure within approximately 25–30 minutes, bonding to the substrate and providing crack-bridging capabilities even in sub-zero temperatures.
Scope Of Works
The works were delivered in three phases. To minimise disruption, hand tools were used to strip the roof back to the metal deck in sections.
The Weproof 264 system was installed with a temporary timber hard edge to manage any difference in levels where new waterproofing met existing areas.
As the existing profiled EPS insulation was unsuitable for replacement due to alignment risks, WestWood’s technical team specified two layers of PIR insulation – a 40mm layer site-cut to fit tightly within the roof crowns, with a 50mm layer adhered on top. This was installed to improve thermal performance while maintaining threshold heights. The thickness of the upper layer was reduced where walkways were required to maintain drainage and prevent crushing under load.
Existing box gutters were relined with preformed metal sections, waterproofed before installation, and sealed at all joints. At junctions with higher-level cladded walls, new upstands were created using pre-coated bent angles.
Key Constraints
One of the main challenges involved the removal and reinstallation of more than 300 solar panels and approximately 40 air conditioning condensers. As the building relied on solar power during peak times, only one inverter could be isolated at a time, requiring careful phasing. Sections of panels were temporarily removed, the roof refurbished, and panels reinstalled before moving on.
Similarly, the AC condensers were temporarily relocated with careful attention to refrigerant line lengths, airflow, and electrical connections.
Temporary cooling was provided for critical areas and the condensers only moved when necessary.
Phased Delivery
Carefully planned in three stages to minimise disruption and maintain building operations throughout the refurbishment.
Precision Installation
Roof sections were stripped back using hand tools, allowing controlled installation around sensitive areas and existing systems.
Enhanced Thermal Performance
A dual-layer PIR insulation solution was specified to improve energy efficiency while maintaining drainage and threshold heights.
Complex Asset Coordination
More than 300 solar panels and 40 AC condensers were safely removed, relocated, and reinstated through carefully managed sequencing.
What We Delivered
Installed by approved WestWood contractors, Everlast Group, the Weproof 264 system delivered a
thermally upgraded metal roof designed for long-term waterproofing performance. The system’s low
odour and fast-curing properties minimised disruption for British Gas and helped keep the project on
track.
Specified in traffic grey, the membrane provided a seamless finish, fully encapsulating upstands and
extending around new handrail supports. The roof’s surface is complemented by Wecryl 420, a textured
surfacer manufactured in turquoise green, which has defined walkways for safe access and maintenance
of the extensive plant.
The refurbishment’s success, including workmanship and aesthetics, were recognised with a nomination
at the Liquid Roofing and Waterproofing Association (LRWA) Awards 2026. The project was named a
finalist in the ‘Liquid Roofing Project of the Year over 1,000 sq. m’ category.
