Groundworks in Devon & Cornwall

Groundworks costs vary considerably because so much depends on what's in the ground — clay soils, made ground, high water tables and rock all affect the cost of excavation and foundation work. The price of a driveway or patio depends on the material chosen, the area covered, the depth of sub-base required, edging restraints, drainage falls and disposal of excavated material. Drainage work is harder to price off a description than almost anything else because the route, the ground and the connection point all matter. We don't publish stock groundworks figures — every job is priced individually after a site visit. Foundations for extensions are usually priced as part of the overall extension project rather than broken out separately.

Groundworks are often invisible from the street and most don't require planning permission. However, driveways are a notable exception: if you're creating or enlarging a driveway in front of a house in England using a non-permeable surface (solid concrete or tarmac), and it's more than 5 square metres, you need either planning permission or to use a permeable surface. Block paving with permeable jointing, gravel, or resin-bound surfaces are permeable and avoid this requirement. Dropped kerbs onto classified roads (A and B roads) always need consent from the Highways Authority regardless of the driveway surface. Retaining walls over 1 metre in height within 1 metre of a highway need consent, and taller retaining walls may need building regulations approval for structural design. Planning permission for drainage works is rarely required for standard domestic work, though any new connection to the public sewer technically requires consent from the local water authority (South West Water in most of Devon and Cornwall).