TECHNICAL FOCUS
RESITRIX PROVIDES A ROBUST CIF-FUNDED ROOF AT PRINCE HENRY’S HIGH SCHOOL Prince Henry’s High School in Evesham is an Ofsted ‘Outstanding’ Academy for students aged 13 to 18 that has worked collaboratively with chartered building consultant, PR Associates, and roofing systems specialist, Carlisle Construction Materials (CCM), to secure a Condition Improvement Fund (CIF) grant for a roof upgrade.
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he project involves a thermal upgrade to three roof areas, totalling 1100m2, along with an overlay with CCM’s RESITRIX system; a single-layer system that combines bitumen and EPDM roofing technologies. The roof refurbishment also involves improvements to drainage to address issues with ponding water. Despite the challenges of the pandemic, the project is now well underway, with phases one and two complete, and phase three to take place during the summer break.
Funding bid The school campus is typical of many high schools, with multiple additions to the original main building. Consequently, there are a number of different roof levels
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and roof areas in varying conditions, with a mix of existing coverings that had reached the end of their service life. In some areas, the roof was leaking and a small roof area over the main entrance was in need of particularly urgent attention because rain was draining onto it, resulting in ponding water. PR Associates advocates CCM’s RESITRIX roofing system for school roof refurbishment projects. The hybrid modified bitumen and EPDM membrane offers torch-free installation and a certified service life of more than 50 years. The chartered building consultant worked with CCM to develop a technical specification, which contributed to Prince Henry’s High School’s CIF application.
“We often find that a collaborative approach between the school, the building surveyor and our technical team at funding bid stage is instrumental in outlining the business case for a CIF grant,” explains Paul Simms, Technical Services Manager at CCM. “Carrying out a full condition survey and providing a technical specification at this stage ensures that the bid considers the full scope of works and that the school makes decisions that will reduce future maintenance costs and disruption.”
Site audit and specification CCM’s site audit was carried out with the contractor, AJR, present to establish the existing roof build-up and condition.
The existing build-up is a profile metal deck, with a vapour control layer, 30mm of EPS insulation, 20mm of fibre board and a bituminous membrane. CCM’s technical team carried out penetration tests to ensure there was no water tracking under the existing coverings. The audit revealed that the majority of the roof areas could be overlaid following preparation with jet-washing, with a requirement to cut out blisters in some areas and carry out patch repairs. For a limited area of the roof, the existing bitumen membrane was so degraded that it had to be stripped out and a new air and vapour control layer (AVCL) was installed. For most of the roof areas, however, the audit confirmed that the prepared existing roofcovering could be used as the AVCL. Paul Simms continues: “Compatibility and ease of installation as an overlay are key advantages of the RESITRIX system. This is particularly important for school roof refurbishment projects, because it helps to reduce the length of the programme and potential disruption by avoiding strip-out, provided the existing covering is properly prepared. Using the existing covering as the AVCL also saves
