Do all extensions require planning permission?

Not necessarily. Many extensions to houses can be built under permitted development rights without a planning application, provided they meet the relevant limitations and conditions. However, rights can be restricted or removed in certain areas and for certain types of property. Checking with the local planning authority before proceeding is advisable.

Is permitted development the same as planning permission?

No. Permitted development rights allow certain works to proceed without a planning application, provided that the limitations and conditions set out in planning legislation are satisfied. Planning permission is a formal grant of consent from the local planning authority. In practice, works authorised by permitted development rights do not require a planning decision notice — though a lawful development certificate can confirm the position.

Do permitted development works need building regulations approval?

Yes, in many cases. Planning permission and building regulations are separate regulatory regimes. Works that fall within permitted development and do not require planning permission may still require building regulations approval. Confirmation of building regulations compliance is important for both lenders and future purchasers.

Can permitted development rights be removed?

Yes. Permitted development rights can be restricted or removed by an Article 4 direction made by the local planning authority, by a condition attached to a planning permission, or by the status of the property (for example, a listed building or a property in a conservation area). The history of the property and its planning designations should always be checked.

Can planning issues affect a mortgage?

Yes. Lenders may investigate planning status as part of their due diligence. Issues such as an unauthorised change of use, outstanding enforcement action, unimplemented planning conditions or a mismatch between the approved plans and the existing use can delay or prevent mortgage lending. A solicitor and, where appropriate, a specialist planning adviser should be consulted.

What is a lawful development certificate?

A lawful development certificate (LDC) is a formal decision by the local planning authority confirming that a proposed or existing use or operation is lawful. It can provide important evidence for both sellers and lenders that works have been carried out lawfully. There are two types: one for proposed development and one for existing development. Obtaining an LDC is advisable where permitted development rights are relied upon and certainty is needed for lending or sale purposes.

Property Knowledge Hub

Planning Permission and Permitted Development Explained

A practical introduction for property investors, landlords and developers in England — covering planning permission, permitted development rights and why planning status matters for property finance.

Last reviewed: July 2026

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Introduction

Property alterations can affect the value, use and financeability of a property. Before carrying out an extension, conversion or change of use, it is important to establish whether planning permission is required or whether the works may fall within permitted development rights.

Planning permission and permitted development are separate from building regulations approval. A project may not require a planning application but may still need building regulations approval, party wall advice, landlord consent, lender consent or another form of approval.

This guide focuses on planning rules in England. Requirements differ in Wales, Scotland and Northern Ireland. Local-authority requirements can also vary, and planning policy and permitted development rights can change over time.

What Is Planning Permission?

Planning permission is formal approval from the local planning authority (usually the local council) for certain developments, alterations or changes in the use of land or buildings. Without the necessary permission, carrying out development can result in enforcement action and may affect the marketability and financeability of a property.

The following types of work may require planning permission, depending on the circumstances:

New buildings
Material changes of use
Larger extensions
Converting buildings into additional residential units
Some HMO conversions
Significant external alterations
Works affecting listed buildings or properties in conservation areas

This is not a definitive list. Whether planning permission is required will depend on the specific circumstances of each project. Advice from a planning consultant or the local planning authority should be sought before proceeding.

What Is Permitted Development?

Permitted development rights allow certain works to be carried out without submitting a conventional planning application, provided that all relevant limitations and conditions are satisfied. The rights are set out in the Town and Country Planning (General Permitted Development) (England) Order 2015 and have been amended on a number of occasions.

Permitted development rights are not an automatic exemption in every case.

Rights can be restricted or removed because of:

The type of property (rights may not apply to flats, maisonettes or some other excluded buildings)
An Article 4 direction made by the local planning authority
A planning condition attached to an earlier permission
Conservation-area status
Listed-building status
Previous development already carried out at the property
The proposed size, position, height or materials
The proposed use of the property

Common Projects to Investigate

The following types of work are frequently undertaken by property investors and landlords. The notes below are a general introduction only. Whether any particular project requires planning permission will depend on the specific circumstances. You should confirm the position with the local planning authority or a planning consultant before proceeding.

Official Resource

Explore the Planning Portal Interactive House

The Planning Portal's Interactive House provides visual guidance on common household projects, including planning permission, permitted development rights and building regulations.

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Planning Permission and Property Finance

Lenders and their professional advisers are likely to consider planning status when assessing a property as security or a development as a viable project. Uncertainty about planning status can delay or prevent funding.

A lender or its professional advisers may investigate:

Whether the existing use is authorised
Whether proposed works have the necessary consents
Whether planning conditions have been discharged
Whether the property matches the approved plans
Whether a conversion has been lawfully completed
Whether enforcement action is possible
Whether the proposed use is acceptable under the lender's criteria
Whether planning permission is required before development funding can be released

Evidence Investors May Be Asked to Provide

Depending on the transaction, a lender or broker may request some or all of the following:

—Planning decision notices

—Approved plans

—Building regulations approvals

—Completion certificates

—Lawful development certificates

—Listed-building consent

—Evidence that planning conditions have been discharged

—Existing and proposed floor plans

—Details of the intended use

—Professional reports where appropriate

Related Knowledge Hub Guides

HMO and Property Licensing Explained

Frequently Asked Questions

This guide is provided for general information only. It does not constitute legal, planning, tax, valuation or financial advice. Requirements can vary according to the property, its location, its use and the proposed transaction. You should obtain advice from an appropriately qualified professional and confirm current requirements with the relevant authority.

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Key Points

—Guide focuses on England
—Rules differ in Wales, Scotland and N. Ireland
—PD rights can be removed or restricted
—Planning ≠ building regulations
—PD rights do not apply to all property types
—Lenders assess planning status

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