Planning Breach Enforcement Landlord Guide 2026 — Enforcement Notices, Limitation Periods, Appeals and Criminal Liability

Common landlord planning breaches and the LPA's enforcement toolkit

Understanding what constitutes a planning breach and the range of tools the LPA can deploy is essential for assessing enforcement risk:

• Common planning breaches relevant to landlords: Under s.55 of the TCPA 1990, 'development' includes: (a) building, engineering, mining, or other operations on land; and (b) the making of any material change in the use of land or buildings. Common breaches landlords encounter: (i) Converting a C3 dwelling (a single dwelling) to a C4 HMO (a house in multiple occupation — 3-6 unrelated residents) without planning permission — in most parts of England, this conversion is a permitted development right and does not require planning permission. However, where the LPA has made an Article 4 Direction removing that permitted development right, planning permission is required for C3→C4 conversion. Conversion of a dwelling to a sui generis HMO (7+ residents) always requires planning permission, regardless of Article 4 Directions; (ii) Operating short-term holiday lets — the Levelling-up and Regeneration Act 2023 introduced a new C5 use class for short-term let dwellings in England from 5 April 2024 (the Use Classes (Amendment) (England) Order 2024). Converting a property from C3 (dwelling) to C5 (short-term let) is a permitted development right — but LPAs in London can designate areas where planning permission is required; (iii) Extensions, outbuildings, and loft conversions beyond permitted development limits (height; size; distance from boundary; coverage ratios — as set out in the Town and Country Planning (General Permitted Development) (England) Order 2015); (iv) Breach of planning conditions — using a property for a purpose not authorised by the planning permission; failing to comply with pre-commencement conditions; using materials not approved by the LPA
• LPA enforcement tools — from least to most severe: The LPA's enforcement toolkit progresses from information-gathering to formal enforcement: (a) Planning Contravention Notice (PCN — TCPA 1990 s.171C): a formal notice requiring the alleged developer/landowner to provide information about the alleged breach within 21 days. Failure to respond to a PCN (or providing false information) is a criminal offence (fine up to £1,000 for failure to respond; unlimited fine for false information); (b) Breach of Condition Notice (BCN — TCPA 1990 s.187A): a notice issued directly by the LPA (no requirement for notice of any kind to the landowner before service) requiring compliance with a planning condition within a specified period (minimum 28 days). Failure to comply with a BCN is a criminal offence (unlimited fine); (c) Enforcement Notice (TCPA 1990 ss.172-182): the principal enforcement tool. An enforcement notice: describes the breach; requires the specified steps to remedy the breach; specifies a compliance period (minimum 28 days). An enforcement notice takes effect 28 days after service (unless an appeal is lodged — see below). Non-compliance is a criminal offence; (d) Stop Notice (TCPA 1990 s.183): issued in conjunction with or after an enforcement notice; requires the breach to stop immediately (or within a specified period, minimum 3 days). The LPA must pay compensation if the Stop Notice is subsequently withdrawn or quashed on appeal — this financial risk makes LPAs cautious about using stop notices; (e) Temporary Stop Notice (TCPA 1990 s.171E): lasts up to 28 days; used for urgent situations; no compensation payable if withdrawn or quashed; (f) High Court injunction (TCPA 1990 s.187B): the LPA can apply to the High Court for an injunction restraining any actual or apprehended breach of planning control. Can be obtained without notice (ex parte) in urgent cases; breach of injunction is contempt of court (unlimited fine; imprisonment)

Limitation periods, Certificate of Lawful Use, and appeal procedure

The limitation periods and the enforcement notice appeal procedure are the two most powerful tools in a landlord's planning enforcement defence:

• Limitation periods — when enforcement action is time-barred: The TCPA 1990 (as amended) provides two key limitation periods: (a) For operations on or in a building (e.g., extensions; conversions; structural works that constitute 'operations' under s.55): 4 years from the date the operations were substantially completed. If the LPA does not issue an enforcement notice within 4 years of substantial completion, the development becomes immune from enforcement — it is lawful as a matter of planning law, regardless of whether it ever had planning permission; (b) For any other breach of planning control, including: a change of use (including C3→C4 HMO conversion; C3→C5 short-term let conversion; any other material change in use); the operational use of a building or land that is the subject of a change of use; breach of a planning condition — 10 years from the date the breach first occurred (i.e., 10 years from the first day of the use change or the first day of the condition breach). If the LPA does not issue an enforcement notice within 10 years of the first day of the breach, the breach becomes immune from enforcement. Importantly: the limitation period runs from the date the breach FIRST occurred — not from when it was discovered or reported. If a landlord converted a property to HMO use 11 years ago (without planning permission in an Article 4 area) and the LPA only discovers the breach today, the breach is now immune from enforcement
• Certificate of Lawful Use or Development (CLU) — confirming immunity: Once a breach has become immune from enforcement (because the limitation period has expired), the landowner can apply to the LPA for a Certificate of Lawful Use or Development (CLU). A CLU confirms in writing that the use or development is lawful — either because it had planning permission, or because it is now immune from enforcement by virtue of the limitation period. A CLU is valuable because: (a) it gives the landowner certainty — removing the risk of an enforcement notice (even after the limitation period, some LPAs may still serve an enforcement notice hoping it is not appealed); (b) it is registerable as a land charge and passes to future buyers — the property can be sold with the benefit of the CLU, giving the buyer confidence in the lawfulness of the use; (c) lenders typically require evidence of lawful use before mortgage lending on properties with potential planning breaches. CLU applications are made on Form 1APP to the LPA; the fee is the same as for a householder planning application. The LPA has 8 weeks to determine the application
• Appeal against an enforcement notice — procedure and grounds: An enforcement notice can be appealed to the Planning Inspectorate (PINS) within 28 days of the date of service of the enforcement notice. Lodging an appeal automatically suspends the enforcement notice — the landowner is NOT required to comply with the notice during the appeal period, and the LPA cannot take enforcement action for non-compliance during the appeal. The appeal is therefore a very powerful tool — it gives the landowner time to negotiate with the LPA, apply for retrospective planning permission, or make the case that the breach has not occurred or that the enforcement notice was procedurally flawed. Grounds of appeal against an enforcement notice include: (a) Planning permission ought to be granted for the development — a 'deemed application' for planning permission; if the inspector grants planning permission on this ground, the enforcement notice falls away; (b) The breach of planning control alleged has not occurred; (c) The notice was not served in accordance with the requirements — procedural invalidity (most enforcement notices are not quashed on procedural grounds alone); (d) The requirements of the notice exceed what is necessary to remedy the breach or prevent injury to amenity; (e) The period for compliance is too short; (f) The enforcement notice was served before the LPA had carried out sufficient investigation. If the enforcement notice is not appealed within 28 days, it takes effect — and the landowner must comply with its requirements within the compliance period (typically 1-6 months). Non-compliance with an enforcement notice after it has taken effect is a criminal offence under s.179 TCPA 1990 — with an unlimited fine. The LPA can also carry out the required steps itself (direct action) and recover the costs from the landowner as a civil debt. Criminal liability under s.179 attaches to the 'owner' of the land — landlords who have sold the property subject to an enforcement notice remain potentially liable for non-compliance during the period when they owned it

Frequently asked questions