Extensions Question


what is the maxium size for a rear single extension before putting in for planning something is telling me around 3m square.
can someone give me some imput regards.

5 Answers

Best Answer

You can build a porch with external measurements not exceeding 3 square metres without planning.
As for larger extensions, if your home hasnt previously been extended, you may not need planning under permitted development.
However, you are going to need buildings regs done, which will normally be with your local council, and they will then inform you if you need planning.
You may have to do a set of drawings of your proposed developement, all this can be done under a building notice.
This is case in the Cotswolds, but other councils may differ.
Best really to have a meeting with your building control, they are helpful and will advise.
Dont go ahead without any agreement in writing, as some have, and have had to pull their work down.

Answered 15th Apr 2011


Member since 29 Oct 2008

yes you can build upto 3 sqare metres without planning or building regs porches ect you dont have to getplanning permissionin alot of cases some times will have to submit a building notice where you can do a sketch of proposedwork and send to local planning where they will give youa decision within 21 days also if not sure about anything the local planning will send aplanning oficer out to explain any queries

Answered 15th Apr 2011

dpc builders

Member since 18 Nov 2010

3 metres long and the width of you house

Answered 15th Apr 2011

Michael Murphy Builder

Member since 26 Nov 2009

I think permitted development is 15% of the floor area of your house the house has not been extended before,regards, Terry.

Answered 16th Apr 2011

tm property services

Member since 9 Mar 2011

what you are talking about are permitted development rights. first you should check that you have them. some areas there are restrictions. if you do then you are allowed to build 3m off the back, full width of the property. but if its a semi or detached house then you might find that planning will let you go more than 3m. if you have any questions feel free to ask.

Answered 20th Apr 2011


Member since 27 May 2010

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