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Case Study

Seamless Pitch-to-Flat Conversion for School

Garland UK Technical Manager
Daniel Sandell

Approved Contractor
Accurate Flat Roofing Ltd

Seamless Pitch-to-Flat Conversion for School

Garland System

StressPly Flex Plus

Sector

Education

Following the successful refurbishment of four roofs at Parmiter’s School in Watford, Synergy Construction once again entrusted Garland UK to deliver a transformative pitch to flat roofing solution. This new project involved converting a leaking metal pitch roof into a durable, multi-layered bituminous membrane flat roof system. Designed to enhance occupant safety, improve durability, and significantly boost energy efficiency, the project was integral to safeguarding the school’s infrastructure and long-term operational costs.

The roof refurbishment was funded through CIF and managed by Synergy Construction, with Garland UK tasked with developing a sustainable and regulatory-compliant roofing solution. A thorough roof condition survey, conducted by Garland UK technical manager Daniel Sandell, provided critical insights into the existing structural and thermal challenges, laying the foundation for a highly effective solution.

Challenge

The 2,742m² roofing area presented a host of interconnected challenges, demanding a comprehensive and innovative approach. The metal pitch roofs were plagued by severe water damage, with poorly constructed frames detaching from structural joists. This not only exacerbated leaks but also created dangerous wind uplift risks, threatening the safety of the building’s occupants and further destabilising the structure.

Thermal inefficiency was another pressing issue. The roof’s insulation significantly underperformed, with a U-value of 3.36, well above regulatory limits, resulting in considerable energy losses and inflated operational costs. Addressing this deficiency was crucial to ensuring the building’s compliance with modern energy standards and improving overall environmental performance.

Additionally, outdated Georgian-wired roof lights and asbestos-containing materials in the perimeter fascia introduced significant safety and environmental hazards. Resolving these multifaceted challenges required Garland UK to leverage its expertise in technical roofing solutions and system design alongside the collective team’s ability to address these critical issues without disrupting the school’s operations.

Solution

Garland UK-approved contractor Accurate Flat Roofing worked closely with Synergy Construction to implement a phased approach to the pitch to a flat roofing project, ensuring the school could remain fully operational throughout the project. This careful planning allowed each roofing section to be addressed systematically while mitigating water ingress during the works.

The existing chipboard and woodwool deck was overlaid with 18mm marine-grade ply. The overlay method in Garland’s design specification ensured the new plywood decking was applied through the chipboard and into the joist, enabling the approved contractor, Accurate Roofing, to install the system quickly while keeping the building dry from the elements.

By retaining the existing structure rather than removing it entirely, this solution minimises waste and disruption. A self-adhesive vapour control layer was then added to reduce fire risks, a crucial safety measure given the composition of the original deck materials. To further enhance the roof’s performance, a tapered insulation system was installed to improve energy efficiency, followed by a base sheet to bond with the final layer.

The final layer consisted of Garland’s BBA-certified StressPly Flex Plus torch-on cap sheet, renowned for its exceptional durability and waterproofing capabilities. This system was backed by a 25-year Single-Point Guarantee, providing long-term assurance for the school. Additionally, the outdated Georgian-wired rooflights were replaced with modern triple-skinned polycarbonate units, eliminating safety hazards and improving the quality of natural light within the building.

Outcome

Throughout the project, Daniel Sandell visited the site twice weekly to oversee the installation process, ensuring adherence to Garland UK’s high standards. Regular progress updates were provided to all stakeholders, including school business manager Jon Whitehouse and Synergy Construction, via Garland UK’s RAMP system, fostering transparency and collaboration.

The pitch-to-flat roof transformation delivered remarkable improvements in thermal efficiency for Parmiter’s School, achieving a U-value of 0.18, the regulatory standard. This upgrade significantly enhanced the school’s energy efficiency, reducing operational costs and environmental impact.

In line with the school’s sustainability goals, Garland UK’s high-performance tapered waterproofing design avoided over 70 tonnes of waste being sent to landfill by eliminating the need for complete roof material removal.

Today, Parmiter’s School staff and students benefit from a robust, low-maintenance roofing system designed for long-term performance. Backed by Garland’s 25-year Single-Point Guarantee and PartnerCare service, the school can move forward with confidence, knowing their roofing system will provide safety, durability, and efficiency for years to come.

The transformation of our school’s roof has been remarkable. Garland UK’s thoughtful technical approach and smooth project management tackled our long-standing waterproofing and energy efficiency issues while keeping disruptions to our operations minimal. Their focus on safety, sustainability, and long-term performance shines through in every detail of the project. With their tailored solutions and dedicated support, Garland has significantly enhanced the safety and environmental standards of our facility, delivering a durable and future-ready roofing system.

Jon Whitehouse

Seamless Pitch-to-Flat Conversion for School

Garland Technical Manager

Daniel Sandell

Approved Contractor

Accurate Flat Roofing Ltd

Technical Manager Daniel Sandell worked with Synergy Construction, converting a school’s leaking metal pitched roof into a durable, multi-layered bituminous membrane flat roof system

Quick Facts

Garland System

Dura-Coat

Sector

Residential

Project Saving Cost

£900,000

The storm exposed critical weaknesses in the original roof design, which had failed to cope with the site’s wind load demands. The closure meant immediate loss of revenue, reduced access to community leisure facilities, and growing urgency to reopen.

The replacement roof required complex engineering to match the building’s 40 metre wide dual-curved structure. Standing seam sheets up to 22 metres in length had to be precision-engineered off-site, with escorted delivery, timed road closures, and careful sequencing of work.

With only a small car park as the site compound, storage, crane operations, and contractor access needed meticulous planning. Moisture protection for the exposed structure was critical throughout, with temporary coverings installed until the new system could be sealed.

Garland UK Technical Manager Rob Wall specified the R-MER LOC standing seam metal system, designed for storm resilience, thermal efficiency, and long service life in marine climates. Its penetration-free, zip-free seam design enabled faster installation and allowed for thermal movement without panel distortion.

The system was tailored to the building’s complex geometry, with 22 metre top sheet runs and 18 metre lower runs. Approved contractor, Future Roof Leeds, carried out the works, reusing the existing perforated aluminium liner where possible to reduce waste and disruption.

A high-performance, foil-lined vapour control layer was installed, along with upgraded insulation and a breather membrane suitable for coastal exposure. Acoustic infills were also integrated to maintain internal sound control, enhancing the original system’s acoustic performance.

The 1,200 sqm roofing system was completed on time and within budget, restoring full functionality to SC2 Water Park and preventing further loss of income. Garland UK’s Roof Asset Management Programme (RAMP) now provides the Council with a complete digital record of the project, including inspection reports, guarantees, and maintenance guidance, giving estates teams full visibility for ongoing asset care.

Covered by a 30 year Single-Point Guarantee for design, materials, and workmanship, the Council has complete assurance that any issues will be resolved swiftly, without dispute or additional cost.

The reopening of SC2 Water Park has reinstated a much-loved leisure venue for residents and visitors, supporting local wellbeing, tourism, and economic activity. The storm-resilient design means fewer disruptions and reduced maintenance, and reliable year-round availability, even in challenging weather.

Robin Jones, Senior Building Surveyor at Denbighshire County Council, commented,

“The level of service from Garland UK has been first-class from start to finish. Rob and the team gave us confidence at every stage, from design to handover. The quality of the roof and the management of such a tricky site exceeded our expectations.”

Rob Wall, Technical Manager at Garland UK, added,

“This was a demanding brief in a harsh environment. The combination of curved geometry, extreme sheet lengths and complex logistics called for precision planning and strong collaboration. We’re proud to have supported the Council in getting this key venue back up and running.”