John Lewis - Kingston Upon Thames with Noxite

John Lewis: Delivering Performance, Sustainability, and Cost Certainty

Discover how a collaborative approach between John Lewis, Icopal, and roofing contractors RTL delivered a successful re-roofing program for a key London store.

The Challenge

Water ingress and standing water plagued much of the roof, with significant blistering, cracking, and a buildup of organic material supporting algae and plant growth. The need for urgent remedial work was clear.

Beyond the roof's condition, the store's unique location beside the River Thames, with a public road passing beneath, presented major challenges. Restricted access and ongoing maintenance issues, present since original construction, would heavily influence the re-roofing project. Given the access and location, safety was paramount. Roofing contractors RTL implemented rigorous safety procedures. Since the store remained live throughout the project, the team also had to ensure the safety of staff, visitors, passers-by, and road users, meticulously preventing debris from falling onto the street below.

The Solution

To guarantee reliable, long-term performance, the RTL team selected an Icopal torch-on bitumen system, finished with a Noxite capsheet.

The comprehensive waterproofing system features multiple layers, including insulation and a bituminous underlay and cap sheet. For sections of the roof directly above the live road, a different strategy was adopted: parts of the existing roof were overlaid rather than fully replaced. We also designed and installed a bespoke tapered insulation scheme. This custom solution directly addressed areas prone to ponding water, which had previously encouraged plant growth.

Beyond delivering a proven, high-performance solution, the addition of the Noxite capsheet significantly enhances sustainability. Its unique granules actively remove harmful nitrous oxides from the air, transforming them into harmless nitrates that are washed away with rainfall.