Garland UK Technical Manager
Daniel Sandell
Approved Contractor
Richard Soan Roofing Services
Garland System
StressPly Flex Plus
Sector
Education
Size
3000 sqm
Project Cost Saving
£98,000
Waste Avoided
30 tonnes
West Ewell Primary School, part of the Bourne Education Trust, is a thriving community school and nursery in Surrey that includes a specialist centre for children with communication and interaction needs. Following years of water ingress issues at the school, Synergy Construction and Property Consultants instructed Garland UK Technical Manager, Daniel Sandell, to conduct a detailed roof survey to evaluate the overall condition and remaining life expectancy of the roof areas and make recommendations for repair or replacement.
The existing built-up bituminous membrane system had come to the end of its natural life and was in extremely poor condition, including areas of poor drainage, organic growth, and ponding water. The protective mineral slate on the membrane had washed away over the years, leaving the cap sheet brittle from unprotected sun exposure and less responsive to movement in the building.
Daniel Sandell identified that whilst the roof was at the end of its natural life, fortunately, it was suitable for an overlay system rather than a costly entire roof strip and replacement. To improve the drainage, the refurbished roof system would also include a tapered warm roof design around the sump outlets.
The StressPly Flex built-up membrane system (BBA-certified) was specified to overlay the 930 sqm roof to deliver a thermally efficient, fully waterproof warm roof refurbishment. StressPly Flex is a high-strength torch-on bituminous waterproofing system designed with superior tensile and tear strength for optimum waterproofing performance.
The Approved Contractor, Richard Soan Roofing Services, got to work preparing the roof by removing the hazardous existing coping stones and debris and plywood board capping the parapets. Torch Flex, a high-performance VCL, was installed, and an additional 90mm flat board and drainers were added to bring the total u-value to 0.18 W/m2K.
A Torch Flex Ultra Vent underlayment sheet was installed before finishing with the StressPly Flex 4.2mm bituminous slate finished cap sheet. The parapet walls were encapsulated with the StressPly Flex system and completed with a GRP Trim.
To complete the works, the aged and underperforming rooflights were removed and replaced for improved thermal efficiency, increasing the volume of natural sunlight for the classrooms below.