Traditional Cornish granite cottages were built using locally quarried granite, often with very thick walls and small windows. The walls are typically solid (not cavity) construction, which requires careful consideration when adding extensions. The granite itself is very hard and durable, but the lime mortar used in traditional construction is softer and more flexible than modern cement mortars.
Many traditional granite cottages in Cornwall are listed buildings or located in conservation areas or AONBs, where planning permission is required for extensions. Planning applications must demonstrate that the extension is sympathetic to the character of the original building and the wider setting. Pre-application advice from Cornwall Council is strongly recommended.
Extensions to granite cottages must be designed to be sympathetic to the original building. This typically means using matching or complementary materials, keeping the scale of the extension subordinate to the original building, and avoiding designs that would detract from the character of the cottage. A good architect with experience of historic buildings is essential.
The choice of materials for granite cottage extensions is critical. Matching granite is the ideal choice for walls, but can be expensive and difficult to source. Alternatives include lime render, natural slate and traditional timber. Modern materials such as uPVC windows are generally not appropriate for granite cottage extensions.
Extending a granite cottage requires careful structural assessment. The existing granite walls may need to be reinforced to support the additional load of the extension. The connection between the old and new structure must be carefully detailed to prevent differential settlement and water ingress. We always work with structural engineers on granite cottage extension projects.
Traditional granite cottages were designed to breathe, using lime mortar and plaster that allows moisture to move through the walls. It is essential that any extension work maintains this breathability. Using cement mortars or impermeable renders on traditional granite walls can cause serious damp problems. We always use appropriate lime-based materials on traditional buildings.
Improving the energy efficiency of granite cottages requires a careful approach. Traditional solid granite walls have poor thermal performance by modern standards, but insulating them internally or externally can cause problems if not done correctly. The extension itself should be built to current building regulations standards, but the interface with the existing building must be carefully managed.
A.V.A Building & Construction Ltd have extensive experience extending traditional granite cottages across Cornwall. We understand the specific challenges of working with historic buildings and always use appropriate materials and methods. Contact us for a free consultation on your granite cottage extension project.
A.V.A Building & Construction Ltd have extensive experience extending traditional granite cottages across Truro, Falmouth and surrounding villages in Cornwall. As members of the Guild of Master Craftsmen, all our work is fully insured and guaranteed.
Contact us today for a free consultation on 01872 719546 or email avabuildingltd@outlook.com.
