Planning Enforcement — What Happens If You Build Without Planning Permission?

Planning enforcement is the process by which a local planning authority (LPA) investigates potential breaches of planning control and, where necessary, takes action to remedy them.

• **Who can trigger enforcement?**
• Enforcement investigations are triggered by:
• •Complaints from neighbours
• •Reports from council officers during routine inspections or other visits
• •Discovery during conveyancing (when a buyer's solicitor discovers works without planning permission)
• •Discovery during a Building Regulations inspection

• **Is enforcement automatic?**
• No. Enforcement is a discretionary power — the LPA is not required to take action in every case. Government planning guidance states that enforcement action should only be taken where it is 'expedient' to do so, having regard to the development plan and all other material considerations. In practice, LPAs are more likely to take action where:
• •The works are highly visible from the street
• •The impact on neighbours is significant
• •The development is substantial (not a minor extension)
• •A formal complaint has been received

**What enforcement action can be taken?** The main enforcement tool is an **Enforcement Notice** — a formal notice served on the owner and/or occupier requiring them to remedy a breach of planning control within a specified period (typically 28 days to several months). An Enforcement Notice specifies what the breach is and what must be done to remedy it — which may be demolition, modification of the works, or cessation of a use.

• Other tools include:
• •**Breach of Condition Notice (BCN)**: where a planning permission has been granted subject to conditions, and those conditions have not been complied with
• •**Stop Notice**: an emergency power to stop ongoing development while enforcement is investigated (rarely used)
• •**Injunction**: the most powerful enforcement tool, available where there is an immediate threat to amenity or where an Enforcement Notice has been ignored

**The key protection for homeowners: time limits on enforcement action**

English planning law contains time limits beyond which enforcement action cannot be taken. After these periods expire, the development becomes 'immune' from enforcement:

**Four-year rule** (for operational development — i.e., building works): Enforcement action cannot be taken against a building, engineering, mining, or other operation in, on, over, or under land after 4 years from the date the operations were substantially completed.

In practice: if you built an extension or converted a loft more than 4 years ago and have been using it since, enforcement action is time-barred. The development is immune.

**Caveat**: the 4-year clock starts from 'substantial completion' — not when you moved in or received the final invoice, but when the building operations were substantially completed. And if the development was deliberately concealed, the clock may not run until the LPA has a reasonable chance to discover it.

**Ten-year rule** (for changes of use): Enforcement action cannot be taken against a change of use of a building to use as a single dwellinghouse after 10 years from the date of the change of use.

For material changes of use other than to a single dwellinghouse, the 10-year rule also applies.

**Limitation Act note**: from April 2024, the Levelling Up and Regeneration Act 2023 changed the enforcement period for operational development from 4 years to **10 years** for new breaches. Works completed before April 2024 are still protected by the 4-year rule. Works completed after that date will need 10 years to become immune. This is a significant change for homeowners — check the current law for your project.

**What happens once time-barred?** Once enforcement is time-barred, the LPA cannot serve an Enforcement Notice. You can apply for a **Certificate of Lawfulness of Existing Use or Development (CLEUD)** to formally record the immune status of the development. A CLEUD is highly recommended before any sale of the property.

If you have built without planning permission and enforcement is not yet time-barred, you have two main routes to regularise the position:

**Route 1: Retrospective planning application** You can apply for planning permission after the works are built — this is a 'retrospective planning application'. The LPA will determine it on the same basis as any other planning application. If granted, the works are regularised.

Important: a retrospective planning application is treated the same as any other application — it may be refused. If refused, the LPA may then serve an Enforcement Notice.

**Route 2: Modify or remove the works** If the works are not regularisable (e.g., a large extension that has significant impact on neighbours, or works in a protected area that cannot be consented), the most straightforward option may be to modify or remove the relevant works.

**What to do if you receive an Enforcement Notice**: 1. Do not ignore it — an Enforcement Notice that is not complied with can lead to prosecution and an unlimited fine 2. Read it carefully — the notice specifies what breach it alleges and what must be done 3. Consider an appeal — Enforcement Notices can be appealed to the Planning Inspectorate on several grounds (e.g., the development is not a breach; the development is lawful; the time for compliance is too short) 4. Take professional advice — contact a planning consultant or solicitor

**The appeal period**: an Enforcement Notice does not take effect until the appeal period expires. Appeals must be made within 28 days of the notice being served.

Planning enforcement issues most often come to light when a property is being sold. This is because:

• •Buyers' solicitors routinely carry out local authority searches, which reveal any registered Enforcement Notices or planning history
• •Sellers are expected to disclose material planning issues
• •Mortgage lenders and buyers' solicitors will raise questions about any extensions, conversions, or changes of use without obvious planning history

• **What a buyer's solicitor will look for**:
• •Planning permission for any extensions, loft conversions, or outbuildings
• •Building Regulations completion certificates for structural works
• •Lawful Development Certificates for Permitted Development works
• •Any history of enforcement investigation or notices

• **How to prepare your property for sale**:
• •If you have extensions or conversions built within the relevant limitation period without permission, obtain an LDC or a retrospective planning permission before marketing
• •If the works are time-barred (built 4 years ago for pre-April 2024 works), obtain a CLEUD — it provides the formal evidence the conveyancer needs
• •If you are unsure of the planning history, a planning consultant can carry out a review

RCB Design & Build works with clients on pre-construction compliance as well as build delivery — if you have an unresolved planning position, we can help you understand your options before works start.