Brims Construction were appointed by Durham University following a competitive tendering exercise in August 2022 to carry out the refurbishment works to Grade I Listed Norman Chapel. Norman Chapel was built in around the year 1080 and is the City’s oldest standing building. Over the years, the Chapel has become partly subterranean due to ground level rises, meaning water from the soil underneath the Chapel has seeped into the sandstone walls and caused structural damage. The restoration works will prevent further damage from occurring and preserve the Chapel keeping its unique features intact.
The works Brims have undertaken at Durham Castle included the following:
Chapel refurbishment: Brims worked closely with Hirst Specialist Conservation contractors, to deliver the provision of floor protection, wall protection, temporary power and access systems. We worked with Tobit Curtus on the monitoring and protection of the environmental conditions during the conservation works. Brims installed 28nr 14 meter long bore drilled piles (to the top terrace of the Bishops garden area of the Castle) to provide a retaining structure to allow the removal of the earth to a depth of just over 5 meters. We excavated by hand with a full archaeological watching brief, the ventilation void to the gap generated between the Norman Chapel wall and the newly created pile foundation retaining structure.
North Range Descale, clear out and repoint, including stone replacements: We Installed a fully designed and fully independent scaffold system for access to 7 working lifts at a length exceeding 30 meters, on the top terrace of the garden area to the rear of Durham Castle. We then carefully removed the cement pointing to over 400m2 of stone façade, with a linear meter of over 3000 meters, carefully removing and replacing over 80 individual stones, window head hood moldings and window cills. Then we carefully removed and replaced parapet wall merlon stones and copping stones, while removing and rebuilding a stone chimney. Using a bespoke lime mortar mix as designed by “The Scottish Lime Trust” directly for use in this one situation.
Window Repair: Working on 17 windows and 1 door to the North Range Façade that was constructed in the 1500’s as part of the Castle, from different designs such as Gothic or Norman Arch, the full refurbishment of the windows, included stripping back the paint layers to bear timber, replacing the timber with like for like materials (mainly oak), easing and re hanging the windows with the correct lead balance weights, to then fully re decorate. There was an element of internal works to these windows. So, we needed to provide a system of protection/ control and coordination to fulfil these works. We needed to work with The Castle Curation team to ensure that all artefacts were considered and protected prior to works being undertaken. We needed to consider the potential of disruption to the University users by material movements, working background noise, and the potential of the fire alarm system being triggered.
Norman Chapel External Wall: This part of the project required us to replace over 60 individual stones to the Norman section of the Castle, these works were the underground / subterranean walls that have recently been excavated and re surfaced. Including the removal of the loose mortar within the Norman Stone wall works and re seal with a bespoke lime mortar mix (designed by Durham University for the sole use in this location). Fill voids with a stone and lime mortar Galletting method, as directed by Durham University Conservation Team.
External Drainage: We installed a full and newly designed Wavin “Root Guard” drainage system, this system has been used in this location and is still freshly designed by Wavin, the system provides a full root guard within the materials, this system has been agreed to become a case study for Wavin.
External Surface water Lead and Cast Iron: During the North Range façade works the old lead rainwater system and down commers were fully removed and refurbished. These works were completed by a specialist contractor with hidden detailing to increase the longevity of the items upon their reinstallation.
Jacobean garden wall reinforcement and re build including the remaking of half rounded stone copings: The engineers provided a reinforcing scheme where bed joints were to be taken out and stainless-steel reinforcement rods placed within the structure, then discreetly re pointed and the junctions / cracks locally made good. There were sections of wall that needed to be taken down, cleaned and rebuilt, in a bespoke brick bond. This also included getting new stones hand cut and finished to re seal the top of the wall.
Underpin of Stone abutment to Castle wall: As the works progressed, we uncovered a section of the castle that had been constructed later in the Castles life but without a foundation of the same proportion as the rest of the localised wall. We had to engineer a system of temporary support to protect the building and the workforce. We had to develop a system of inspection and monitoring during these works for the completeness of careful control to these works.
Testimonial: “Very rewarding but challenging scheme – unsupported buttress needed underpinning upon excavation externally, repairs and maintenance to the north façade and excavating down to provide a ventilated light well to stop the deterioration of stone within the chapel- mainly from excessive moisture moving from the external walls through to the interior affecting the coal measures sandstone. Thanks to the project team who are doing a fantastic job on a complex project.” Ian Rooney, Director of Construction Services, Durham University