Do I need planning permission?

Most projects come down to a short list of factors. Get these clear early and the conversation with a planning officer, architect or Building Control becomes far quicker and far less speculative.

Permitted development rights are a general allowance, not a guarantee attached to a category of building. They can be reduced by an Article 4 direction covering an area, removed by condition on an individual planning permission, or restricted because the property has already used up part of its permitted development allowance with earlier extensions. None of that is visible just by looking at the building.

This is why a neighbour's identical-looking extension is not evidence of what your property is allowed. Planning history is checked property by property.

If a project looks likely to fall within permitted development, the safe next step is a Lawful Development Certificate application to the local planning authority, which gives a formal, checkable answer rather than an assumption.

If a project looks likely to need full planning permission, the next steps are usually a pre-application discussion with the authority, an architect or planning consultant to prepare drawings and a supporting statement, and — in designated areas — an early view on materials and design approach before drawings are finalised.

If the property is listed, listed building consent is a separate legal requirement that sits alongside (not instead of) any planning permission needed, and applies to internal as well as external works in many cases.

An Article 4 direction is a specific legal instrument a planning authority can use to remove some or all permitted development rights across a defined area — a Conservation Area, a group of streets, or a whole settlement. Where one applies, work that would be permitted development anywhere else needs a full planning application instead, and the direction itself has to be checked with the local planning authority; it will not necessarily be obvious from looking at a property or a map found online.

Article 4 directions are used more often in areas the authority considers sensitive to incremental change — historic town centres, Conservation Areas with a strong uniform character, and some National Park settlements. If a property sits in or near a Conservation Area, checking for an Article 4 direction is worth doing before any permitted development assumption is relied on.

A Lawful Development Certificate is not only for proposed work. A Certificate of Lawfulness for Existing Development (sometimes called an established use certificate) confirms that something already built or already in use is lawful — typically because it has stood, unchallenged, for a period set out in planning law, or because it was granted permission that can be evidenced. This matters most often at sale, when a buyer's solicitor asks for proof that a garage, extension or change of use was lawful at the time and remains so.

Without a certificate, an unauthorised structure or use can remain a live enforcement risk indefinitely in some circumstances, and can complicate or delay a sale. Where the history of a structure is unclear — no planning decision on file, no dated evidence of when it was built — resolving that before marketing a property, rather than after an offer is agreed, avoids last-minute complications.

Planning enforcement is discretionary, not automatic, but it is a real risk, not a theoretical one. An authority that receives a complaint, or notices unauthorised work during an unrelated site visit, can investigate and — depending on the harm it considers the development causes — require alterations, refuse retrospective permission, or in serious cases require demolition or reversal of the work.

A retrospective planning application can be made once work has started or finished, but it carries no better chance of success than an application made in advance, and it is made from a position of no leverage: the authority already knows the work exists and there is nothing to negotiate on design before it is built. Lenders and buyers also treat unauthorised work as a risk at sale, sometimes requiring indemnity insurance or a retrospective certificate before completing.

SHS is the contractor, not the planning authority. What SHS can do is look at what you are proposing from a build point of view — access, ground conditions, levels, drainage, foundations and buildability — and tell you plainly what the construction side is likely to involve.

If drawings already exist, send them. If they do not, a site visit and a conversation usually establishes what information you need to gather next and who you need it from.