Dyffryn House

VaultStone restored Dyffryn House façades, delivering cleaning, masonry and Bath limestone repairs, stainless steel pinning, dormer reconstruction, blending traditional craft with conservation techniques to safeguard building.

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Built 1891-3 in a style derived from French Renaissance and English Baroque, the architects are said to be Habershon and Fawckner of Newport. The building is of random quarried stone construction, with a smoothed down stucco plaster finish and Bath limestone features.


 

As a specialist subcontractor to one of the UK’s premier heritage main contractors, our team was entrusted with the targeted repair of the external façades of a historically significant property. This work was guided by a comprehensive condition survey carried out by the National Trust’s professional team, ensuring that all interventions were sensitive to the building’s architectural and cultural value.

Our scope included the meticulous restoration of masonry, stonework, and decorative elements, with a focus on preserving original materials wherever possible. Using traditional techniques alongside modern conservation methods, we addressed structural vulnerabilities and aesthetic deterioration while maintaining the integrity of the façade.

The project demanded close coordination with conservation specialists, heritage architects, and site managers to ensure compliance with conservation best practices and statutory requirements. Our contribution helped safeguard the building’s character and longevity, reinforcing its role as a cherished part of the UK’s built heritage.

To facilitate safe and efficient access to all elevations, the building was enveloped in a multi-lift access scaffold. Prior to the commencement of repair works, the façades were sensitively cleaned, revealing the true condition of the building fabric and allowing previously unidentified defects to be addressed. This preparatory step was crucial in refining the scope and ensuring that all necessary repairs were captured.

Our team undertook the restoration of masonry, stonework, and architectural detailing using traditional techniques and compatible materials. The work was executed with precision and care, preserving the building’s historic character while enhancing its structural integrity and visual appeal.

As is so often the case when refurbishing and repairing stonework on historic buildings, while the scope of the works is well known, the volume of that identified scope grows exponentially, in order to realise the planned refurbishment.

We completed numerous high quality and invisible, in-situ plastic repairs, necessary to mitigate the damage caused by wind driven pooled water. We dismantled and repaired chimney tops, replacing failed flaunching and indenting damaged Bath limestone.

Our skilled team of masons defrassed and repointed the sandstone plinth and raked out and made good the pointing to the fine dressed Bath limestone.

We provided sample mortars for approval by the National Trusts professional team and on the sandstone used proprietary mortar blend to match the existing pointing aesthetic. On the Bath limestone a mortar from natural hydraulic lime and graded limestone dust was used to match the existing. Throughout the scheme, and as directed, we introduced stainless steel pinning to failed stone components such as window heads and lintels to mitigate further movement and stabilise the structure.

The roof level, stone fronted dormers on the south elevation were in poor condition and corroding ironwork within the roof structures had begun to impact the masonry, jacking lintels and displacing pediments. The pediments were dismantled, as far as necessary, in order to remove the corroding iron. they were rebuilt with new stone to replace that that had been damaged beyond reasonable repair. Iron was replaced with graded stainless steel and lead flashings were redressed to new chases.

The variation in repairs that required new stone was considerable. From simple 6 sided indents to scrolled brackets on the underside of raking pediment projections; from huge but simply moulded plinth blocks, to return and break handrails; the handrails were supported variously, with 3 different shapes of

balusters, including small and large traditionally profiled cylindrical, and short, similarly squared profiled. All these replacement stone interventions were painstakingly recorded, templated from similar moulds, and where necessary 3D scanning was performed to record profiles and to facilitate modern day CNC machining processes.

Throughout the contract, working diligently with the MC, liaising with the National Trust and their professional team we delivered another quality product, using traditional and heritage skills and a modern supply chain. Providing an outstanding project, that will serve to further extend the life of this glorious and historic building.

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