Permitted development conditions and the effect of a breach

A permitted development condition breach does not leave you with a small problem on one part of the work. It usually leaves the whole extension unauthorised. The right to build came from the General Permitted Development Order, that right was granted subject to conditions, and if a condition is not met the development falls outside the class. There is no planning permission to fall back on.

That is harsher than most householders expect, and it is why the obscure glazing on a side window matters as much as the depth of the extension.

Limitations and conditions do different jobs

Open Schedule 2, Part 1 of the GPDO 2015 and each class has two sets of text under it.

The limitations, numbered A.1, B.1 and so on, define the boundary of the class. Depth from the original rear wall, eaves height, the proportion of the garden covered, whether the land is in a conservation area. Exceed a limitation and the development was never permitted development at all.

The conditions, numbered A.2, A.3 and the equivalents, are requirements that attach to development which does fall within the class. Materials of similar appearance to the existing house. Upper floor side windows obscure glazed and non opening below 1.7 m above the floor. A roof enlargement set back from the original eaves. The restriction on cladding materials on land in a conservation area.

The practical difference is small, because the outcome of failing either is the same. The drafting difference matters when you are reading the Order, since people check the dimensions carefully and skip the paragraph underneath.

What happens the moment a condition is broken

The extension becomes unauthorised development. All of it.

Install a clear opening window at first floor in the flank wall of an otherwise compliant rear extension and you have not built a compliant extension with one non compliant window. You have built an extension that does not benefit from Class A, because the condition attached to the whole class was not met.

Councils vary in how they describe this, and the point has been argued more than once. What is consistent is the consequence for the owner: there is no permission for the works, and the position is only cured by obtaining one or by removing what was built.

The good news is that the fix is often trivial. Replace the glass with obscure glazing to the required level and fix the window shut below 1.7 m and the condition is met from that point. A council that receives a complaint will usually ask for exactly that before considering anything formal.

Enforcement, and the time limits that apply

Enforcement is discretionary. A planning authority takes action where it considers it expedient, and a minor technical breach that has been corrected rarely gets further than a letter.

Where it does proceed, the routes are an enforcement notice under section 172 of the Town and Country Planning Act 1990, requiring steps to remedy the breach, or a planning contravention notice first to establish the facts. Appeal against an enforcement notice goes to the Planning Inspectorate, and the grounds include that planning permission ought to be granted.

Time limits changed recently and the detail matters. The historic position gave four years of immunity for operational development such as building work and ten years for most other breaches. The Levelling-up and Regeneration Act 2023 extended the operational development period in England to ten years, with the change taking effect in April 2024 and applying to breaches from that point. Check the date the change came into force against the date your works were substantially completed, because the applicable period depends on it.

Immunity is not approval. It means the council can no longer require removal, and establishing immunity still requires evidence.

Retrospective permission as the remedy

Section 73A of the 1990 Act allows an application for planning permission for development already carried out. In practice this is the normal route once a breach is identified and cannot be corrected by adjustment.

Three things to understand about it:

1. The council assesses the development on its planning merits, exactly as if it had been applied for in advance. The fact that it is built carries no weight in its favour.
2. The matters the Order kept out of consideration are now fully in play. Design, overlooking, the effect on the street scene, parking. Permitted development spared you that assessment, and a retrospective application reopens all of it.
3. A refusal leaves the development unauthorised and gives the council a stronger position on enforcement.

A planning statement explaining why the works accord with the local plan and the relevant design guidance is worth preparing properly, because a retrospective application that reads as an apology rather than an argument tends to attract objections.

Where a lawful development certificate fits

A certificate of lawfulness is the only formal way to establish that works are lawful. Nothing else binds the council.

Section 192 covers proposed development, so you can establish before building that the scheme falls within a class and meets its conditions. Section 191 covers existing development, used either to confirm that completed works were permitted development or to establish immunity through the passage of time.

The certificate application needs the evidence, not the argument. Dimensioned drawings of the existing and proposed building, a measured survey of the original dwellinghouse as it stood on 1 July 1948 or as first built, and for a section 191 application dated evidence of when the works were completed. Invoices, dated photographs, utility records and a statutory declaration all help.

Householders often ask whether a planning officer's email confirming the works look acceptable is enough. It is not. Informal confirmation has no legal effect and officers change jobs.

The conditions householders miss most often

From the pattern of enforcement cases rather than any one survey:

The driveway one catches people constantly, because the work is done by a contractor who has never read the Order. The condition is satisfied either by a porous surface or by directing runoff to a permeable area within the curtilage, and a block paved drive draining to the road meets neither. The piece on air source heat pumps and permitted development limits sets out the equivalent traps in Part 14.

Permitted development rights removed by planning condition

Worth checking before anything else on a house built in the last thirty years.

Article 3(5) of the Order provides that permitted development does not apply where the development would be contrary to a condition imposed on a grant of planning permission. Conditions removing Class A, B and E rights are standard on new estates, on barn conversions and on houses in sensitive settings.

Find the original permission on the council's online register and read every condition. An Article 4 direction does the same thing across an area rather than a single site, and both are easy to miss because neither appears on your title deeds. The planning law timeline is where to follow changes to the Order, and the list of supporting reports shows what a retrospective or full application typically needs behind it.

Checking the position before anything is built

Measure the original house, not the house as it stands today. Read the class, then read the conditions under it. Check the planning history for conditions removing rights and check whether an Article 4 direction covers the street. Then, if any of it is marginal, apply under section 192 before the builder starts.

A certificate costs a fraction of a rebuilt roof.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.

Enter your postcode on PlanScope to see which documents a retrospective or full application for your extension would need.