Case Studies


Girdlestone Estate

The success of the Girdlestone Estate refurbishment project was recognised at the 2018 Roofing Awards, when it won the Reinforced Bitumen Membranes category. The housing estate had suffered from water ingress issues, and these were successfully resolved by Langley’s design and specification, installed by Opus Waterproofing Solutions Ltd, a Langley Approved Contractor.

During the 1990s, a shallow pitched metal butterfly roof with in-built gutters was installed onto all Girdlestone Estate properties. However, defects in the roof’s design, combined with the age of the system, led to leaks, affecting both the homes and their occupants. Despite continual repair work, issues with the roof persisted. Islington Council therefore decided that a full replacement of the 3,600m2 roof would need to be undertaken, in order to permanently fix Girdlestone Estate’s failing system.

In order to make an informed decision about the type of roofing system that should be installed, Langley, along with Opus Waterproofing Solutions, conducted a full assessment of the existing roof. The team removed a section of the roof to inspect its state and decipher the best way of approaching the project - they discovered that the mineral wool insulation within the old system was completely saturated and needed to be replaced.

Langley’s TA-20 - a premium high-performance torch applied SBS elastomeric membrane for warm roofs – was the chosen solution. Due to the water damage found on the original roof, the new system had to be carefully considered to ensure that no further issues would ensue. The TA-20, which is part of the Langley Parafor range, is durable, yet flexible and the heavy-duty polyester composite metal lined vapour barrier provides a robust, watertight layer, preventing water damage and any leaks to the below structure, whilst the works are ongoing.

The system’s 40 year life expectancy was a key consideration in the decision for TA-20, along with its certifications; the membranes used for TA-20 are covered by MOAT 31, the assessment for Reinforced Homogeneous Waterproof Coverings of SBS Elastomer Bitumen, and the Parafor Solo Cap Sheet, which is the outer layer of the TA-20 system, achieves a “resistance to damage” rating of R4 under MOAT 31. The system also carries a 20 year independently insured guarantee for both materials, design and workmanship. After the many years of issues, it was vital that the chosen roof for Gridlestone Estate could provide a long-term solution, to ensure that residents did not experience any further disruption.

Gary Chapman, Group Leader, Capital Programme Delivery at Islington Council, said: “The Girdlestone Estate has been a priority for the council and we knew that Langley – working with our service provider Mears - could be trusted to work closely with our technical team to carry out an extensive survey to reveal the underlying issues with the roof.”

Work on the roof took place as part of a broader refurbishment of the Girdlestone Estate, with Mears Group PLC carrying out the external works at the same time. The project as a whole was completed on a tight time schedule, which demanded challenging lead times for Langley.

Langley’s extensive roof refurbishment experience ensured that a suitable plan was put in place to keep the work running to schedule and without problems. Langley used the initial block, as well as its extensive knowledge of roof types across London, to gain calculations for the tapered insulation, roof lights and outlets. The team could then create these elements for the remaining 19 blocks ahead of time. This ensured that the construction team could remove the existing metal butterfly roof and instantly replace it with the new TA-20 system, without the need for a temporary solution.

The team also utilised a rolling programme, which enabled communication between the client and contractor. This was vital for the success of the build and allowed for the original roof to be inspected on the day that it was being replaced. The team was then able to make adjustments without causing major disruption to timescales.

David Hodgson, Executive Managing Director at Mears Group, added: “With such a challenging project, Langley’s support throughout the refurbishment was invaluable and the solution they provided will ensure that the estate’s roofs are protected from any future problems.”

Main System Products:

  • Adepar JS
  • Paradiene [35] S R4
  • Parafoam Ultra
  • Parafor Solo
  • GS ParaTrim
  • Parevapo SBS


Balcony Products:

  • Paracoat Embedment Coat
  • Langley GFM Embedment Fleece
  • Paracoat Top Coat
  • Lang-Tile


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Further Information

Find out more about our roofing services by calling us on 01327 704778 or emailing us at [email protected]

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