NFRC logo
Roofing news and information from NFRC

How Kemper System restored a Festival of Britain gem

3 mins

A popular East London church built in 1951 was suffering from severe leaks from a failing asphalt roof until its repair with Kemper System’s solvent-free and odourless liquid waterproofing solution.

calvary charismatic baptist church roof

The manufacturer’s Stratex Warm Roof system and Kemperol 2K-PUR liquid waterproofing solution was specified to refurbish the Calvary Charismatic Baptist Church in Poplar.

The church, which was experiencing severe water ingress due to the failure of the existing asphalt waterproofing and glass skylights, was built in 1951 as a ‘live architectural exhibition’, part of the Festival of Britain. The building is a heritage site with an unusual design to the structure of the roof.

For many years, financial challenges meant the church had to carry out temporary repairs, which included a timber structure built over the entire roof area, and a felted covering on top of the original roof surface.

The initial single-ply specification was changed to Kemper’s Kemperol 2K-PUR by architects, A&RME, to provide a liquid waterproofing solution capable of addressing the complex design of the building with its concrete gutters and columns, as well as a number of round rooflights–meaning Kemper System’s seamless waterproofing solution was ideal for the level of detailing required.


calvary charismatic baptist church membrane roof

The Stratex Warm Roof system, comprising Kempertherm insulation and Kemperol 2K-PUR cold applied liquid waterproofing membrane, was quick and easy to apply, minimising possession times on site and allowing the community to enjoy the church at its best once more.

Roofing contractor Capital Roofing Co. of Blackheath in Greenwich, installed the roof system, which involved removal of the timber structure and felt layers to reveal the 40 original circular skylights.

The contractor then applied a primer and vapour control layer, followed by a hard-top insulation board over the whole roof area. The build-up included a substantial amount of insulation to fill the void in between the concrete beams. Insulation was also installed to the upstands of the beams and walls, and a cut to falls scheme was laid over the whole roof area to reroute the drainage into the existing side concrete gutters.

The Kemperol 2K-PUR liquid waterproofing system was then installed on the flat roof area, providing a seamless membrane around the skylights and around the concrete upstands. A bespoke, aluminium trim was then fixed to cover the insulation and the Kemperol 2K-PUR system at all the abutments.

calvary charismatic baptist church roofing skylights


Commenting on the project, Chris Shulver at Capital Roofing Co. said: “This was a challenging refurbishment not only because the church is a heritage site, but also due to the amount of detailing required with its 40 circular skylights. A long-term waterproofing solution was needed following many failed refurbishment attempts in the past, using alternative waterproofing systems. We have installed Kemperol many times before and its versatility made it the ideal choice.

A temporary roof had to be erected prior to installation of the system to help keep the building as watertight as possible. Thanks to Kemperol’s quick and easy application, we could tackle the high level of detailing required on site with ease. It also decreased the time required for the temporary roof because of the single, wet-on-wet application process that doesn’t require the base coat to cure before subsequent site visits and further coatings are applied, unlike wet-on-dry systems.

Steve Henderson, technical manager at Kemper System, added: “We worked closely with Capital Roofing and architects, A&RME, to develop a specification which met the needs of the project and we are delighted with the result.

The Stratex Warm Roof system and Kemperol 2K-PUR liquid waterproofing solution was a perfect choice for the church, and it’s completely odourless solvent-free qualities were a bonus for the contractors and congregation alike.

Share this article…