What building work can I do without planning permission?
Permitted development (PD) rights allow a range of building work without the need for a formal planning application. For a standard dwelling, a single storey rear extension that does not exceed 4 metres from the original rear wall (detached house) or 3 metres (semi-detached or terraced) is usually permitted development. Larger extensions — up to 8 m (detached) or 6 m (attached) — may be possible under the Prior Approval process but require an application to the local planning authority.
Double storey extensions always require full planning permission, regardless of size. There is also a general rule that extensions must not cover more than 50% of the curtilage (the land around the original house, excluding the footprint of the house itself).
Loft conversions using Velux-style rooflights are typically permitted development on any roof slope. Rear dormers are usually also PD, but front dormers require full planning in most cases. Like-for-like roof replacements do not require planning permission or building regulations approval (though a new roof structure does need building regs).
Properties within Dartmoor National Park are managed by the Dartmoor National Park Authority (DNPA) — a separate planning body with significantly stricter controls. Properties in the North Devon Coast AONB, Cornwall AONB areas or a conservation area have reduced PD rights. Torridge District Council (which covers Holsworthy), West Devon Borough Council in Devon and Cornwall Council all have their own guidance online, and pre-application advice is available from each.
As part of a free site visit we can talk through whether your project looks like permitted development or whether a full application is likely to be needed — no fee, no obligation.