Purcell has lead the delivery of an extensive programme of restoration works at Durham Cathedral which draw on all our core disciplines in Architecture, Masterplanning and Heritage Consultancy.

Working with the Cathedral for over 7 years, Purcell have been involved in Open Treasure - a world-class exhibition experience funded by the National Lottery Heritage Fund which has transformed the how visitors experience the site.

Our various projects across the Cathedral have increased accessibility and made use of previously hidden spaces whilst celebrating the architecture of the building.


Durham Cathedral is the largest and finest example of Norman architecture in England. Initially commissioned to assess potential improvements to the use of space on Durham Peninsula World Heritage Site, Purcell has had the privilege to be involved in Durham Cathedral’s Open Treasure project since its inception in 2010.

Since then our team of architects, masterplanners and heritage consultants has applied its combined expertise on four phases of work undertaken to fulfil the Dean and Chapter’s vision: to widen public access to the cathedral’s hidden treasures, which include architectural spaces as well as pieces from the collection. The process included extensive expert research coupled with valuable programmes of consultation and public engagement.

Rigorous understanding of context formed the foundation of all decision making, articulated in a suite of documents that included two key reports: The Framework Conservation Management Plan – that established a structure for understanding the historical development, significance, conservation need and capacity for change across the cathedral site. And the Quinquennial Inspection Report - that identified the urgent need to address both conservation and repair of the claustral building and significant improvement in the environmental conditions within which the collections were stored.

Through this research it became apparent that the greatest potential for spatial improvement and accessibility lay in those buildings and spaces that surrounded the cloisters, which despite being of outstanding value were largely inaccessible and in urgent need of repair, resulting in four distinct interventions.

Durham Cathedral © Andy Marshall

Monk’s Dormitory

The late fourteenth-century Monk’s dormitory is one of the most spectacular mediaeval English halls. The long oak-beamed room is the last monastic dormitory intact in England. It was once divided into narrow cubicles in which the Benedictine monks studied and slept. Functioning as a library since 1856, it is now also an exhibition space displaying Durham Cathedral’s collection, a narrative interactive exhibit and objects like Anglo-Saxon stones. The project made the space accessible and engaging, with a new lift and lighting design, while retaining its use as a working library.

The Great Kitchen

The Great Kitchen was built in the fourteenth century and is a rare example of a Medieval English monastic kitchen. The spectacular space has a distinctive octagonal ceiling and high rib-vaulted ceiling and is now the home of Anglo-Saxon ‘Treasures of St Cuthbert’ display. The conservation project consisted of significant restoration of the decaying stone of the roof vault and walls and the installation of a new limecrete floor.

The internal environment was improved to provide stable and safe conditions for the fragile Saxon silks, manuscripts and artefacts. The interior was relit to display the architectural and archaeological qualities of the room.

Cathedral Shop and Restaurant

We created a new shop within the 13th-century undercroft. The minimalist design of new glazed screens enhanced the Medieval architecture, as well as creating an enjoyable space for the shop and restaurant. We followed the cathedral tradition of designing the fittings and using the in-house team to manufacture the furniture. Great care was taken over lighting and new materials to ensure fit within the historic context.

Collections Gallery

The collections gallery showcases precious artefacts in a state-of-the-art gallery, renovated with exceptionally high levels of environmental control and security. From the Collections Gallery a new stair and lift and opened passageway leads to the Great Kitchen Exhibition space; this required complex archaeology and dismantling of low significance fabric.

Library and Reading Room

The Refectory Library contains the cathedral's collection of rare early printed books, housed in the former Medieval refectory, re-fitted in the early 18th century.

We have stabilised the environmental conditions including humidity, temperature and UV light to ensure the protection of the valuable books and manuscripts to be read in the adjacent space, a new Reading Room.


From the start, a key aim of the project was to include the volunteers, Friends of Durham Cathedral and wider community in shaping and supporting the project; the success of the project has relied on the enthusiastic support of the volunteers. The successful outcomes of the project are the repair and preservation of the heritage, as well as making the spaces and collections accessible to all who visit the Cathedral.

The project has led to range of community engagement activity projects, as well as arts related projects now a part of the displays. The project has had a beneficial improvement in the cathedrals educational offer to schools and incorporates a space for school and education activity. There is an increase in visitor numbers to the region, supported by other tourism offers that supports the wider regeneration of the region.

The project has also provided the basis for heritage skills and skills training. The new exhibition spaces are now offering the community to see and enjoy their heritage, both spaces and collections in a new and meaningful way. A number of jobs have been created through the project to support the delivery of the activities and offer to the community. The Open Treasure Project was officially opened by HRH The Prince of Wales on 13 February 2018; this was a major celebration for the Cathedral, City and wider regional community.


Construction materials divided into two categories. Interventions were executed in contemporary modern materials, such as low iron, low reflectance structural glazing with natural metal detail; this enabled a clear distinction between old and new, and created clear visibility of the heritage without distraction. Lighting was a key component in revealing the form and surface of the historic spaces.

Materials for repair were complex; analysis of the historic lime mortar confirmed that it contained magnesium from its magnesium limestone base, this has reacted with atmospheric sulphates to create a highly soluble and damaging salt that resulted in stone decay. The poor environmental conditions within the space resulted in these salts oscillating between the soluble and crystalline state and therefore was resulting in surface deterioration. A range of different lime repair and lime mortar techniques were used to consolidate the surface and manage moisture migrations without further decay. This comprised lime putty, hot lime and NHL. Much of the repair was carried out by the in-house masonry team whole were trained through the project in the use of hot-lime technique. Some very limited stone renewal took place; a stone of matching geology, strength, chemistry and visual character was identified as an outcrop of the existing stone type which is no longer quarried locally. Much of the stone decay was repaired using stone slips and lime mortars. Repair is always honest, whilst seeking to maintain the overall special character of the historic building and conserve in-situ the upstanding above ground archaeology of the fabric.

The implementation and site coordination of the project had to be carefully managed around the live site and ongoing life and activities of the cathedral. Archaeological investigation and excavation was a major consideration that was incorporated into the project programme.

Internal lobbies

In February 2020 Purcell completed the internal lobbies to Durham Cathedral’s north and south doors which marks the final stage of the cathedral’s Open Treasure project.

The lobbies delicately frame the architecture of doors, improve visitor access whilst maintaining the environmental conditions inside the space. Their transparent and minimalist design opens up visibility inside the church and onto the Cathedral’s cloister.

The newly renovated Durham Cathedral enhances its position as a focal architectural destination of the North of England. The Open Treasure project has created new access to Durham Cathedral's hidden architecture and artefacts.