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Ian Smith, Associate Chartered Building Surveyor, shares a recent project challenge from the team.

The project below demonstrates the importance of fully establishing the condition of an existing building, before undertaking a major refurbishment project, allowing for necessary repairs to be made and making sure the building is suitable for future use. 

The Project

When York Conservation Trust acquired the building from City of York Council in January 2015, a major internal redevelopment was due to commence in just a few months time.

The project, which cost over £4 million, addressed many issues on the interior of the building. The new owners, York Conservation Trust, were also concerned with the condition of the roof and ensuring all external fabric was secure for the future.

The Brief

We were commissioned to carry out a detailed Condition Survey of the external fabric to establish the extent of the work required. We identified that extensive re-roofing was necessary to safeguard the integrity of the building and protect the new work to the interior.

The Challenge

Overall the roofing project covered around half an acre, with a complex structure that included, steep roofs, flat roofs and awkward geometries with areas that were very difficult to access – it is actually as much a landscape as a roof.

As a result the project was very challenging, particularly as much of the work was carried out late Autumn and Winter. The complexity of this refurbishment became instantly apparent with the results of the initial survey, conducted by myself on behalf of the York Conservation Trust.

The area that presented the biggest challenge was the flat roof above the atrium of the theatre, which was part of a Grade II* Listed 1967 extension designed by renowned modernist architect, Patrick Gwynne.

The Solution

The condition survey revealed that the roof was actually made up of two separate build-ups laid on top of each other. The design team retrieved original drawings from the RIBA archives to find out more. These showed an intention for glass dome roof lights, which would have let light flood into the atrium below. However this had been covered over by a timber roof deck and asphalt. Sadly, these roof lights only acted as a dust trap, becoming discoloured and offering very little light into the atrium.

Thanks to the on-going refurbishment works, we were able to let the original design intention be realised, with new state of the art polycarbonate roof light domes installed. Making a huge difference to the light in the atrium below, we also added colour-changing LED lighting around the inside of the roof lights to create a wonderful feature within the building.