Case Study- St Columba’s, Ripley Street

Project:                St Columba’s, Ripley St

Location:              St Columba’s, Former St Columba’s Church, Ripley Street, Bolton, Greater Manchester, BL2 3AR

Contractor:          Tyson Construction

Roof Size:             484m2

Roof System:       Sika Sarnafil Single Ply Roof, G410-15EL

Installation:         Fully Adhered


St. Columba’s, a former church on Ripley Street, Bolton, underwent a transformation into a modern residential development thanks to the collaborative efforts of Tyson Construction and ours.

Our Role in the Project:

We undertook the installation of Cold Roof balconies, Warm Roof balconies, and a new main roof to breathe new life into this historic site.

Cold Roof Balconies:

For the cold roof balconies, our team meticulously installed a roof deck made from precast concrete planks, ensuring a seamless surface by screeding, or grouting to prevent ridges and hollows.  We then applied the Sika Sarnafil G410-15EL membrane, fully adhered for optimal weather protection. This was reinforced with Sarnafil peel stops strategically placed around the perimeter and roof penetrations. Completing the ensemble, a Sarnafil G445-13 PVC protection sheet was installed, topped with load-bearing strength graded timber decking for a blend of durability and aesthetics.

Warm Roof Balconies:

The warm roof balconies saw the installation of a new precast concrete roof deck, overlaid with a Sarnavap 5000E membrane for superior vapour control. We used Sikatherm PIR insulation, this offers zero Ozone Depletion Potential (ODP) and low Global Warming Potential (GWP), in a staggered bond layout, mechanically fixed for stability. A Sarnafil G410-15EL Light Grey single ply membrane was meticulously adhered to the lower layers, reinforced with peel stops and a protective PVC sheet, ensuring longevity and resilience.

Main Roof:

Installed on the main roof was a new plywood roof deck, mechanically fastened to guarantee structural integrity. We applied a Sarnavap 5000E membrane, followed by Sikatherm PIR GT insulation for optimal thermal efficiency. Finally, we installed a Sarnafil G410-15EL Light Grey single ply membrane, offering excellent weatherproof protection, flame retardancy, wind resistance, and UV resilience.


What was once a historic church, has been transformed into a modern residential development, blending functionality with aesthetics seamlessly. The meticulous attention to detail and choice of high-quality materials ensure that St. Columba’s achieved the 20-year manufacturers guarantee.