Flats and maisonettes

I want to build an extension to my ground-floor flat

Planning Permission

To add an extension to your flat you must apply for planning permission.

If your flat is a listed building it is likely you will need listed building consent and you should contact your local planning authority for advice before you start work.

Works to a listed building that affect its special historic character without consent is a criminal offence.

If your flat is in a conservation area and your proposals involve an element of demolition then you may need to apply for planning permission for relevant demolition in a conservation area and you should contact your Local Planning Authority for advice.

Building Regulations

The majority of extensions or conversions of properties require approval under the Building Regulations. You may need to consult the Fire Service regarding issues relating to fire escapes.

Search and find

Find a professional ^{(https://www.planningportal.co.uk/planning/planning-applications/find-a-trade-professional)}

Find a professional

RTPI Directory of Planning Consultants ^{(https://www.rtpiconsultants.co.uk/#/)}

RTPI Directory of Planning Consultants

Find your building control authority ^{(https://www.planningportal.co.uk/applications/building-control-applications/building-control/find-your-LABC)}

Find your building control authority

Useful links

Make an application ^{(https://www.planningportal.co.uk/app/applications)}

Make an application

Speak to an expert ^{(https://www.planningportal.co.uk/permission/planning-guidance-service)}

Speak to an expert

Studio Charrette consultancy calculator ^{(https://www.planningportal.co.uk/permission/home-improvement/planning-consultancy-calculator)}

Studio Charrette consultancy calculator

Sell your site with Land Match ^{(https://www.planningportal.co.uk/permission/commercial-developments/sell-your-site)}

Sell your site with Land Match

https://www.planningportal.co.uk/permission/common-projects/extensions/is-building-regulations-approval-needed-for-an-extension

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