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Planning permission and building regulations

An extension or addition to your house is considered to be permitted development, not requiring an application for planning permission, subject to set limits and conditions. Visit our interactive house and extensions mini guide to find out about the limitations on size and placement of your planned extension. Most extensions of properties require approval under the Building Regulations.

A planning consultant may help with the smooth running of your project and guide you on your planning permission requirements. To find an accurate consultancy quote, explore Studio Charrette's calculators1.

Explore our interactive guides2

View our extensions mini guide3

The following elements normally have to satisfy the requirements of the Regulations when building an extension:

If in doubt you should always consult your local planning authority.

Find your Local Planning Authority

If your property is a semi-detached or terraced house, you will need to advise adjoining neighbours of your plans under the Party Wall Act 1996.

Find out more about the Party Wall Act 199611

Useful links

Find a Trade Professional

Use our partner directories from RIBA, FMB, or RTPI to find an architect, builder or planning consultant to help with your project or development.

Find a trade professional


Useful links

Interactive guides Common projects Make an application


Planning Consultancy Calculator Financing your project
    1. https://www.planningportal.co.uk/permission/home-improvement/planning-consultancy-calculator
    2. https://interactive.planningportal.co.uk/detached-house/outside/extensions
    3. https://interactive.planningportal.co.uk/mini-guide/extensions-single-storey/0
    4. https://www.planningportal.co.uk/permission/common-projects/doors-and-windows/building-regulations
    5. https://www.planningportal.co.uk/permission/common-projects/drains-and-sewers/building-regulations
    6. https://www.planningportal.co.uk/permission/common-projects/electrics/electric-vehicle-charging-points
    7. https://www.planningportal.co.uk/permission/common-projects/external-walls/building-regulations
    8. https://www.planningportal.co.uk/permission/common-projects/kitchens-and-bathrooms/is-building-regulations-approval-needed-for-work-to-a-kitchen-or-bathroom
    9. https://www.planningportal.co.uk/permission/common-projects/internal-walls/what-building-regulations-apply-to-internal-walls
    10. https://www.planningportal.co.uk/permission/common-projects/roof/roof-planning-permission
    11. https://www.planningportal.co.uk/permission/responsibilities/other-permissions-you-may-require/party-walls

    The Planning Portal is delivered by PortalPlanQuest Limited which is a joint venture between TerraQuest Solutions Limited and the Department for Levelling Up, Housing & Communities. All content © 2022 Planning Portal.

    The Planning Portal is delivered by PortalPlanQuest Limited which is a joint venture between TerraQuest Solutions Limited and the Department for Levelling Up, Housing & Communities. All content © 2022 Planning Portal.