Project Overview
As a Grade 1 listed building since 2015, the British Library is of significant historical value and importance, and maintaining the condition of the roof is crucial. Building Transformation was appointed by the British Library to undertake the roof and gully replacement using Welsh slate and code 7 lead to match the existing and work in line with Historic England’s requirements.
- Removal of all failing and loose Welsh slates across the roof section
- Retaining all slates in sound condition for use and reinstallation
- Mixing of slates prior to installation to blend new and old slates to minimise replacement.
- Removal of failing and defective lead gully
- Refix substructure and refit all slates with bespoke, approved fixings
- Refit all code 7 lead to flashings and gullies, where failing, and finish with patination oil
Project Description
The roof and lead replacement works were fully managed and delivered by Building Transformation, compiling all relevant project compliance and safety management information for pre-approval, project management planning and satisfaction.
Significant detailing was given to the slate and quarry of selection to ensure that the slates were the best match fit for the retained units. The roof is highly exposed to the surrounding environment, blending the replacement, minimising the change and impact was at the heart of the conservation project and worked in line with the philosophies of English Heritage and Historic England.
The lead flashing and lead slate coverings were slowly lifted to enable the safe and delicate removal of all the slates for storage, re-use or disposal. All the slates were removed by a team of specialist heritage roofers and lead workers, and significant attention was paid to the condition of the roof substructure prior to the future planning of the roof placement. Over time, the fixings of the failing and old slates had allowed water to ingress into the roof substructure and penetrate behind the lead gullies and flashing, resulting in defective roof components and systems.
The step angle of the roof created the initial access challenges for the safe removal and storage of the slates, but through detailed working at height, safety planning and consultation with the client, we were able to demonstrate compliant and safe working practices to ensure safe project delivery.
The traditional gullies installed around 1985 were inspected, lifted, cleared and repaired where required, ensuring that both the roof and leadwork defects on the roof were resolved through the project scheme and the roof structure and fixings were sound for years to come.
Project challenges
Built with step roofs, the access challenges not only required highly skilled roofers, but also a team that was fully trained and compliant with working at height practices, working in restraint and rescue planning.
- Grade I listed building, the specific roof and lead replacement requirements had to adhere to the listed building consent and conservation.
- Accessing the roof, removing tiles, stacking or re-selection and lead gullies for replacement and repairs.
- Blending the new tiles with the old to help minimise the impact of the roof replacement
