PROJECT REQUIREMENT
The Chocolate Works in York is the former head office of Terry’s Chocolate Factory, opened by the Terry family in 1926, and now a historic landmark with a Grade II listing. Once home to famous brands such as Chocolate Orange, the factory and offices were closed in 2005 and fell into disrepair over the subsequent decade. In 2009 the old HQ was put on an official at risk register by English Heritage.
Eventually, the building, which is part of a 27 acre site, was acquired by Henry Boot Developments for conversion. One of the key focuses of the work was to preserve and retain the art deco features of the building, whilst increasing its lifespan. A vital element of this would be a full roof refurbishment, including existing flat and slate roof areas that were in a very poor state of repair, and the roof of a new additional floor to the building.
SIKA SARNAFIL SOLUTION
Hull based roofing contractor, L A Hall, was brought on board by principle contractor, Simpson (York) Ltd, to complete the roofing works, which comprised a number of disciplines, including heritage Westmorland slating, single ply, zinc cladding and leadwork. L A Hall was able to offer the level of expertise and skills to complete the entire project, making them the perfect choice.
L A Hall suggested using a Sika Sarnafil system for the flat roof areas, as it matched the client’s requirements for longevity and sustainability, and is the company’s preferred membrane choice. The project’s conservation officer was initially concerned that the system would be too shiny, but Sika Sarnafil provided a number of samples, and after discussions, the specification was accepted without any issue.
The project was complex due to the multiple roof areas and detailing. To begin, the existing slating on the central north light roof slopes, which were remaining in place as part of the new scheme, were re-covered using a fully adhered Sika Sarnafil system including G410-EL membrane in Lead Grey.
In addition to the existing roof areas, an extra floor to the building was constructed around the north lights. Its steep slated mansard-type external elevation included approximately 60 dormer windows, which required zinc on all the vertical faces and Sarnafil on the tops. The flat roof area of the extension was then also covered with the Sarnafil system, along with 140m of parapet guttering detailing, and a new roof terrace area.
Many details had to be considered in order to preserve the original look of the building. For example, the architect and conservation officer required a timber mop roll detail to the perimeter of the main roof and the dormers. All parties, and the Sarnafil team, worked closely to achieve a practical and aesthetic solution, which involved creating detailed life-sized models of key elements. This collaborative and applied approach gave the conservation officer confidence that the detailing was sympathetic to the building’s heritage.
The L A Hall team overcame various challenges, including working on sloped areas, tight time scales and challenging winter weather, but thanks to the skill of the fitters and the flexibility of the Sarnafil system, the project was finished to an impeccable standard, and on time. The newly refurbished roof looks stunning and will defend the building from the elements for many years to come.
The sensitive approach employed throughout this inspiring project has conserved this prestigious feature of York for future generations. The Chocolate Works continues to give back to the community in its new guise, and keeps its famous name as a care village, owned by Springfield Healthcare.
