Planning permission vs permitted development

Two words decide the shape of most London renovations: consent and certainty. Some work can be carried out under national permitted development rights, with no planning application at all. Other work needs express permission from the council, and a good deal of London property sits under additional restrictions that remove the easy route entirely.

This is a plain-English orientation for homeowners in England. It is not a substitute for advice on your particular building, and the rules genuinely do change — your local planning authority is the authority.

Two different systems, often confused

Planning permission governs whether you may change the use or external appearance of a building and how it affects the area around it. Building regulations govern how safely and soundly the work is constructed — structure, fire, insulation, ventilation, drainage, electrics.

They are separate approvals with separate applications, separate fees and separate inspectors. A loft conversion can be entirely permitted development and still require full building control sign-off. Assume you need both until you have established otherwise.

What permitted development typically covers

Permitted development rights are national grants of planning permission set out in secondary legislation. For houses in England they commonly cover, subject to detailed limits and conditions:

• Single-storey rear extensions within set depth and height limits, with a larger allowance available through the prior approval route described below.
• Loft conversions within a stated volume allowance, provided the roof is not extended beyond the plane of the principal elevation fronting a highway and materials are similar in appearance.
• Rear or side dormers and rooflights within those same volume and position rules.
• Porches, outbuildings, hard surfaces, and many types of solar installation, again within limits.

Every right comes with conditions attached — height at the eaves, distance to boundaries, materials, proximity to a highway, the proportion of garden covered. Miss one condition and the whole thing becomes development requiring permission.

Flats and maisonettes are different

This surprises people every week: permitted development rights for extensions and loft conversions do not apply to flats or maisonettes. If you live in a converted Victorian house split into flats, an external alteration will normally need planning permission — and, separately, your freeholder's licence to alter under the lease. Internal reconfiguration usually falls outside planning control, but the lease and building regulations still apply.

When permitted development is taken away

Several common London circumstances remove or narrow those rights.

Article 4 directions

A local authority can issue an Article 4 direction withdrawing specified permitted development rights across an area — frequently in conservation areas, and often aimed at front extensions, roof alterations, windows or the loss of front gardens. Whole streets in inner London boroughs are covered. Check the council's policies map before you assume anything.

Conservation areas

Inside a conservation area the rights that remain are tighter. Side extensions and cladding are typically excluded, roof alterations are heavily constrained, and the authority will apply design guidance on materials, window detailing and the character of the rear elevation.

Listed buildings

Listing protects the whole building, inside and out, and any structure within its curtilage. Listed building consent is required for works affecting special architectural or historic interest — which routinely includes internal partitions, chimneypieces, staircases, floor build-ups, windows and services routes. It is a criminal offence to carry out such works without consent. Listed building consent is required in addition to any planning permission, and the design conversation is longer, more detailed and better served by early engagement with the conservation officer.

Prior approval for larger rear extensions

Houses can extend further to the rear than the standard permitted development depth by using the larger home extension route: you notify the council with plans, the council consults the adjoining neighbours, and if no neighbour objects within the consultation period the extension may proceed under permitted development. If a neighbour does object, the council decides whether the impact on amenity is acceptable. It is quicker than a full application but it is not automatic, and the notification must be made before work begins.

Lawful development certificates: buying certainty

If your scheme is permitted development, you can apply for a Lawful Development Certificate confirming that formally. There is no obligation to do so. There is, however, a very good reason to.

• It is the evidence your buyer's solicitor will ask for at sale.
• It protects you if enforcement is raised later, or if the council's interpretation differs from yours.
• It forces the design to be tested against the conditions before money is spent.

The application is decided on fact and law rather than planning merit, and a well-prepared submission with accurate drawings is usually straightforward. Treat the fee and the wait as insurance.

Building regulations, briefly

Whichever planning route applies, structural alterations, new drainage, replacement windows, electrical work in certain locations, insulation upgrades and anything affecting means of escape require building control approval — either through the local authority or an approved inspector. Work is inspected in stages and closed out with a completion certificate. Keep every certificate: it is part of the value of the house.

A practical order of operations

1. Establish the property's status: house or flat, listed, conservation area, any Article 4 direction.
2. Read the lease if you are a leaseholder, and identify whose consent you need.
3. Have a designer test the scheme against permitted development limits before drawing anything ambitious.
4. Choose the route: permitted development with a certificate, prior approval, full application — or a combination.
5. Prepare a proper application. Weak drawings and thin planning statements cause refusals and re-runs.
6. Run building regulations in parallel, not afterwards.
7. Deal with the Party Wall etc. Act 1996 separately again; it is a civil matter unaffected by planning.

Getting it right first time

Consents are where London projects lose the most time, and where the difference between a considered submission and a hopeful one shows most clearly. We manage the whole route — strategy, drawings, applications, conditions and discharge — as part of planning permissions and approvals, alongside structural modifications where the scheme involves opening up or building out. Timescales are covered in our guide to how long a London renovation takes.

See our projects for schemes delivered through each of these routes, or get in touch with your address and a description of what you would like to do.

Guidance, not advice. Planning legislation, permitted development rights and local designations change, and every property is different. Confirm your position with your local planning authority and a qualified planning professional before committing to a design.