Permitted Development Advice in London

Permitted development rights allow specified works to houses — some extensions, lofts and outbuildings — to proceed without planning permission, subject to limits on size, height, materials and position. They apply to houses, not flats or maisonettes, and they are frequently restricted in sensitive locations. Even where they apply, you usually still need building regulations approval, and it is often wise to confirm the position with a lawful development certificate.

In conservation areas, permitted development is often reduced, and an Article 4 direction can remove specified rights entirely. Listed buildings, flats and maisonettes, and properties with planning conditions are also restricted. We assess your specific property rather than relying on general rules, and advise whether to proceed under permitted development, seek a certificate, or apply for planning permission.

For a house, permitted development broadly covers single-storey rear extensions up to 3m beyond the original rear wall (4m for a detached house); larger rear extensions of up to 6m or 8m under the prior-approval route; single-storey side extensions within width and height limits; roof additions such as rear dormers within a volume allowance of around 40 cubic metres for a terrace and 50 for a semi or detached house; outbuildings; and hardstanding. Each comes with detailed conditions on height, materials and position, and the allowance is cumulative — earlier extensions count against it. We confirm exactly what remains available on your property.

Some of the most useful rights, such as the larger single-storey rear extension, are not pure permitted development but require prior approval: you notify the council, which consults your immediate neighbours, and if they do not object on specified grounds the works can proceed. It is faster and more certain than a full application but is not automatic, and it only assesses limited matters. We advise when prior approval is the right route and manage the notification, so you use the allowance without tripping over its procedure.

Relying on permitted development without documenting it is a quiet risk: at sale, a buyer’s solicitor or lender will often ask for proof that works did not need permission, and an undocumented assumption can stall a transaction. A lawful development certificate is the council’s formal confirmation that the works are lawful, and we generally recommend obtaining one where a project relies on permitted development, so the position is settled in writing rather than argued years later.

PD is not a vibe; it is a legal envelope. We check tenure, designations, planning conditions and cumulative extensions before advising that a rear extension or dormer is permitted. Wrong advice here creates enforcement and sale problems years later.

Larger home rear extensions may use prior approval rather than pure PD. We explain when neighbour consultation applies and what that process does and does not assess.

Even where PD applies, a lawful development certificate is often the wise next step so lawfulness is proven in writing. Buyers’ solicitors and lenders frequently ask for it. We prepare drawings to the precision a determination requires.

Building regulations still apply to most PD works. Planning freedom is not a free pass on structure, fire or insulation.

If the design you need exceeds PD, forcing a cramped PD scheme can destroy the brief. A well-designed householder application is often better value than a compromised box that happens to fit a limit. We present both options with risks, not a single sales route.

Article 4 streets should assume tighter control until proven otherwise.