Repairs and alterations at Sackville House

By architect Nicola Westbury

In autumn 2019 one stone slate slipped from the roof at Sackville House. This small incident set into motion one of Landmark’s most complicated maintenance projects in recent years, ultimately leading to 65 weeks of closure for substantial repair works across the building. Overseen by Landmark’s surveyor for the south Olivia Mayell and facilitating employment for teams of specialists from more than 17 different organisations, the works were possible thanks a grant from the government’s Culture Recovery Fund.

As Sackville welcomes holidaying guests once more, project architect Nicola Westbury and Olivia offer an insight into the rabbit-warren of conservation challenges Sackville presented.

Line drawing plans of the proposed roof alterations to Sackville House

Sackville House lies on the south side of the High Street in the town of East Grinstead in the county of West Sussex. The grade II listed house dates from circa 1525 and comprises the main north range onto the street with a south wing extending into the garden behind, reached via a cross passage through the north range. The garden, with its views south towards the Ashdown Forest, is in an area of former burgage land known as the Portlands. The strips of land were used for domestic agriculture and are a rare survival.

In the spring 2019, the Landmark Trust commissioned me to carry a building fabric survey. The survey found that there was a need to repair the roof members and wall framing and to renew the roof coverings. The locally distinctive Horsham stone slates and the orange red clay plain tiles were failing. There was ongoing consequential damage due to water penetration to the oak roof and wall frame members with some water ingress to the Sackville House interior.

The findings of that survey were brought into sharp focus in autumn 2019, when one of the Horsham stone slates slipped on a Friday afternoon leaving an open hole in the front roof slope. Fortuitously, Clarke Roofing Southern Limited, a family run roofing company based in Eastbourne, East Sussex, had worked recently elsewhere for Landmark. Karl Strudwick, contracts director, arranged temporary protection and a scaffolding the same weekend to protect people from any further falls from the front roof.

What followed was an urgent project whereby Landmark brought forward remedial works. But with holiday bookings for Sackville House having been made already for the next year, and much of their maintenance budget allocated already, the work was not easy to achieve. But, in early 2020, the world changed with the start of the Covid pandemic. The Landmark Trust had to close its holiday properties, so losing much of its income immediately. Despite the situation, that summer, drawings and a specification were prepared for the repairs, listed building consent obtained from Mid Sussex District Council and the building contract negotiated with Clarke Roofing Southern.

Then in the autumn 2020, Sackville House was one of the buildings that received part of the large grant awarded to Landmark thanks to the Department for Digital, Culture, Media and Sport’s Culture Recovery Fund. Although negotiations had been underway already, the grant enabled the roof repair project to go ahead. Employment would be provided for people with specialist skills, so helping the recovery of both the local economy and the heritage sector nationally.

Clarke Roofing Southern commenced construction work in January 2021 to repair the chimneys and some wall frame members, renew the roof coverings, redecorate externally and renew and provide additional rainwater drainage. I was appointed the same month to administer the building contract. Over the first few weeks and then into the spring and summer, it became evident that extensive repairs were needed to enable the roof coverings to be renewed. Additional architectural and structural drawings, a further specification and revised work schedules were prepared, plus a second listed building consent obtained for the additional works.

Below I share a month by month summary progress of the construction works. The photographs, all taken during site visits, show some of the complexity of the building fabric and the intricacy of the repairs. The project team key members are listed at the end too. Karl Strudwick, Dan Sweet and others at Clarke Roofing Southern managed the many Covid restrictions by keeping their specialist skills teams separate. After 442 days of closure, the works were completed onsite in February 2022, following which internal redecoration, furniture repairs and reorganisation and cleaning by Landmark’s operations team enabled Sackville House to reopen for holiday lettings in March 2022.

January 2021

With scaffolding to the north front wall of the north range in situ at commencement, scaffolding to all other walls was erected. The Horsham stone slate and clay plain tile roof coverings were removed and temporary protection provided to the exposed roof members. The construction programme was revised to incorporate the extent of repairs revealed.

Horsham stone is one of the special aspects of Sackville’s architecture, but it’s also one of the challenges. Large scale commercial extraction of Horsham Stone was halted by the 1880s and regular quarrying ceased completely in the 1930s. A small quarry was reopened in 2004 but the thin slabs used for roofing come from the top of the quarry and this has been exhausted. Reclaimed stone does exist, however it is extremely difficult to get hold of and - even then - it is often difficult to trace its origin and identify if it had been sourced ethically.

February 2021

The works were paused whilst a temporary roof was designed. Additional drawings, a specification and work schedules were prepared for the additional works required after the project team visited and identified a whole range of additional problems that needed fixing urgently, including unforeseen chimney, roof, dormer, external wall, window, door and internal repairs. Additional other works included variations to the roof and wall coverings, external decorations, rainwater and foul drainage and the provision of mechanical extract ventilation.

March 2021

The temporary roof erection was completed. The contract variations were priced and works resumed. Preparations were made for the repairs and materials were sourced. The programme was revised twice to include yet further repairs. Materials shortages started having a major impact on the project, affecting red clay roof tiles, nails and timbers.

April 2021

The roof repair preparations continued, especially investigations of the existing hard rendered infill panels and timber decay. Further designs for the additional structural repairs were provided and some roof repair works started.

May 2021

The roof and wall frame oak member investigations continued. Detailed drawings were prepared for the rendered infill panel repairs and renewals. A further programme revision accounted for yet more repairs and for party wall negotiations with the neighbours.

June 2021

The oak roof member structural repairs continued and sheep’s wool insulation was fitted between the rafters. The wall frame oak member and the oak and metal window repairs commenced. The condition of the wall infill panels was inspected. Temporary access scaffolding was erected to the chimneys for inspection of the brickwork condition and the need for repairs.

July 2021

At last, the roof member repairs neared completion allowing other carpentry roof repairs to progress. The chimney brickwork repairs and part rebuilding started. The wall frame oak member repairs were ongoing with some renewal in oak of whole members including the south bressummer over the cross passage. The external decorations began with some high-level window steel frames and the rainwater goods. One of the elements that caused particularly sleepless nights was the new huge rooflight window - because of its bespoke nature, it took 7 weeks to design, 12 weeks to manufacture and 2 days to install.

August 2021

The roof carpentry, insulation fitting, underlay and batten fixing and chimney repairs continued. At long last, the Horsham stone roof slating and leadwork commenced. New rainwater gutters and downpipes were fixed. The recovering of the party wall commenced. The rendered infill panel repairs and part renewal commenced.

September 2021

The Horsham stone roof slating and leadwork continued. The clay plain tiling commenced, the wall frame member repairs too. The chimney repairs and partial rebuilding neared completion. Access was arranged with our neighbours to inspect the north range south wall east part and south wing east wall. We suffered a blow when Clarkes turned up to site one day to find £2,500 of lead had been stolen overnight, just before it was about to be laid. Police investigated but the culprits were not found.

The construction programme was revised yet again as it became clear that the works would not be completed until the new year: the scale was huge, for example there was not an elevation of the building that didn’t need timber repairs. Internally, some decayed and damaged plaster was removed. Extractor fans were fitted to the kitchen, bath and shower rooms. Landmark’s trustees and management staff visited to witness the ongoing work.

October 2021

The Horsham stone slating and clay tiling was completed along the north slope of the north range roof, and the south slope half recovered with the roof windows fitted. The leadwork to the south wing dormers was underway. The wall frame oak member repairs continued. The infill panels were being repaired and renewed in wood fibre sheet with burnt sand mastic joint filler. The new rainwater gutters and downpipes were being fitted. Internally, decayed and damaged plaster and laths were removed.

November 2021

The Horsham stone slating and much of the clay tiling was completed to the roofs. Olivia accurately described the assembly of reclaimed and replaced Horsham stone tiles to be ’like completing a jigsaw puzzle without the final photo’. Leadwork to the chimneys and No 74 gable wall was completed. The wall masonry, frame and panel repairs continued. Internally, the sitting room’s decayed floor joists were renewed. Further decayed and damaged plaster and lathing was repaired. We decide to retain our conservation philosophy of ‘honest repairs’, so not staining timber insertions to match original timbers but leaving them visible to age gracefully and become part of the building’s restoration story.

December 2021

The wall frame oak member and infill panel repairs were nearing completion. The north range cross passage ceiling was being re-plastered in part on new lathing. The oak-frame window repairs continued with the repaired steel frames and leaded glazing refitted. The south wing external doors were repaired. Internally in the basement, insulation was fitted between the sitting room floor joists with new ventilation openings to the cross passage. The plaster repairs were completed. Floorboards were repaired to the sitting room and elsewhere and plans were developed to completely redecorate the interior.

January 2022

The temporary roof was removed, the kentledge (ballast) water drained off and the scaffolding dismantled. The wall frame and door repairs and the cross passage ceiling re-plastering were finished. The interior parts of the building were completed and handed over to Landmark for the commencement of internal decorations. Having visited five or six times during the project, building regulations surveyor Andrew Alford from the local authority made his final visit to site.

February 2022

The north range entrance gate and the cross passage brick and ironstone paving were repaired. The last parts of the works were completed. The site was cleared and handed over to Landmark’s teams. After being covered for over a year, Sackville’s beautiful and rare 16th century wall paintings were once again revealed. The decision is made to install an electric vehicle charging point. It is estimated that the total weight of the new roof is an astonishing 300 tonnes, hoped to last hundreds of years into the future.

Slates tiled roof newly repaired at Sackville House

March 2022

Landmark’s furnishings and regional operations teams spend three weeks preparing the property for the return of guests. New furnishings are introduced throughout and the sitting room layout is revised. One upstairs bedroom is rearranged too. New white goods are installed in the kitchen, including a dishwasher and fridge with better freezer storage. All fittings are cleaned, polished and reorganised, the floors, wood burning stove and garden furniture tended to. As spring unfolds, the garden’s magnolia begins to bloom just as the first guests arrive.

With thanks to 

Many people worked together to contribute to the success of this unexpected major project. Sincere thanks to:

The local neighbours and community in East Grinstead for their patience

Main contractor: Clarke Roofing Southern Limited

Scaffolders: Hailsham Scaffolding Limited

Masons: T E Tilley Limited

Carpenters: HD Building and Carpentry Limited

Lead workers: M Marchant Specialist Lead Roofing Contractors Limited

Structural engineer: Justin McAteer formally of Hockley and Dawson

Timber decay specialist: EBS

Colleagues across Landmark in particular Olivia Mayell, together with Millie Ankers, Steve and Lisa Boland, Patrick Bowens, Susan McDonough, Sally-Ann Nixon, Victoria O'Keefe, Alan Rushmore, Andrew Trigwell and consultant John Evetts.

Timber-framed Sackville House after restoration March 2022