Products Used

Richard Cook, Technical Director at SSQ, explains how quality natural slate helped revitalise a period property in Chippenham.

When it comes to restoring a Grade II listed building, the roof is often the unsung hero.

For Avonbridge House in Chippenham, Wiltshire, a complete re-roofing was essential to preserve its historic character and ensure its longevity.

This ambitious project, undertaken by A L King Roofing Ltd for Alliance Pharmaceuticals, has been shortlisted for a prestigious Pitched Roofing Award, a testament to its exceptional quality and craftsmanship.

Avonbridge House, situated on Bath Road in Chippenham, is not only the commercial home of Alliance Pharmaceuticals but also a Grade II listed building.

This dual status presented unique challenges that required a delicate balance between preserving historical integrity and meeting modern commercial needs.

The project, completed in February 2024, demonstrates how SSQ’s products can rise to such challenges, providing both aesthetic appeal and long-lasting performance.

Restoration required

The decision to re-roof Avonbridge House was prompted by a detailed investigation following repairs to the bell tower in 2021.

This revealed a significant number of broken slates, with many showing signs of delamination and previous reuse.

The existing roof had a mottled appearance due to mixed colour slates, moss, and lichen growth.

It became clear that continued patching would be neither practical nor economical, necessitating a complete re-slating to ensure the long-term preservation of this important building.

Choosing the right product

After careful consideration, SSQ Del Carmen Ultra 500 x 250 slate was selected as the primary roofing material.

The Del Carmen Ultra slate offered a more homogenous and uniform appearance than the existing weathered roof, whilst still respecting the building’s historical character.

The slate had been successfully used on other listed and commercial buildings in the Wiltshire planning area, easing the approval process.

Alliance Pharmaceuticals’ commitment to reducing carbon emissions aligned perfectly with the environmental benefits of Del Carmen Ultra slate, which is ISO 14001 certified.

SSQ’s 100-year labour-backed guarantee provided assurance of the product’s durability and quality.

SSQ offered significant planning and technical support throughout the project.

Challenges and solutions

The installation process presented several unique challenges due to the building’s age and listed status.

The roofing contractors faced the task of working with bowed walls and uneven surfaces, requiring meticulous attention to detail.

The Del Carmen Ultra slate was installed dry-fixed at a 200mm gauge, adhering to BS 5534:14 and BS 8000:13-part 6 standards.

Special care was taken to square the eave chalk line at both the eave and verge, accommodating the building’s irregular shape.

This involved face cutting and fixing slates on raked eaves on both sides of the bowed walls.

To maintain a regular appearance, the perp lines were carefully set out with 3-5mm joints between slates, avoiding any butt-jointed slates.

This attention to detail ensured a uniform and aesthetically pleasing finish, crucial for a listed building of this prominence.

The Riverstone Overlap Ridge and Hips were chosen to complement the Del Carmen slate.

This product allowed for mechanical fixing and dry laying without visible screw fixings, meeting the stringent requirements for listed buildings.

Overcoming logistical hurdles

The project faced significant logistical hurdles due to the building’s location.

The north-facing elevation, fronting a main road, required careful consideration of public right of way.

Meanwhile, the south-facing side backed onto a waterway, limiting access.

To manage these constraints, all materials and storage were located on the south side of the main building, requiring precise planning and coordination.

Despite these challenges, A L King Roofing Ltd completed the project on time, a testament to their skill and the ease of working with SSQ’s products.

Environmental and heritage considerations

The re-roofing project had to balance the need for modernisation with heritage preservation.

The addition of PV panels was carefully integrated into the design, aligning with Alliance Pharmaceuticals’ commitment to reducing greenhouse gas emissions.

The use of Del Carmen Ultra slate ensured that this modern addition did not compromise the building’s historical character.

Whilst the re-roofing represented a change to the heritage asset, it was deemed to cause less than significant harm.

The benefits of using Del Carmen Ultra Slate, including its durability and aesthetic qualities, were considered to outweigh any minor alterations to the building’s appearance.

Moreover, the long-term preservation of the structure from damaging roof leaks was paramount in the decision-making process.

The re-roofing of Avonbridge House demonstrates that with the right products, expertise, and attention to detail, it is possible to honour the past whilst preparing for the future.

As SSQ continues to innovate and provide exceptional slate products, we look forward to contributing to many more such successful restorations across the UK and beyond.

If you’d like to find out more about using SSQ slates for your next roofing project, get in touch today. Call 020 8961 7725, email info@ssq.co.uk or get a quote online.