NEW HOUSES UNDER CONSTRUCTION OFTEN STILL HAVE PERMITTED DEVELOPMENT RIGHTS FOR FURTHER EXTENSIONS OR ALTERATIONS BUT THE TIMING OF IMPLEMENTING THE PD EXTENSION SCHEME IS CRITICAL - GET IT WRONG AND YOU CAN BE IN A HEAP OF TROUBLE:

Many self build home owners or developers want to add an extension to their new home during the construction process of the main dwelling.  Many people see the Permitted Development route as the ideal way of adding extra floor space to the new home economically during the new build of the main home.

This route is riddled with 'technicality traps' that can see you in deep water without a float or a paddle if you get it wrong. Many homeowners have lost a lot of money and time pursuing this 'clever' route to instantly expanding their new home during construction.

One important point to remember is that Permitted Development was never intended to add instant space to a new dwelling under construction.  The spirit of the limited development freedom the government has given ordinary property owners is for a home owner to add space to suit their needs over a period of years of the life of the property rather than a housing developer having instant added profits.  This is perhaps why, many Councils are resistant in helping any 'clever developer' with allowing them to combine two development schemes into the one project. 

Before I explain the safer route to obtaining your objectives you must first understand the technical legal issues that are waiting in the wings to thwart your progress to instant added floor space:-

1 - Many new homes from single dwellings to larger estates often have had the sites PD rights removed on the original Planning Consent.  Therefore your first action is to check that the type of PD extension you wish to build has not been removed by a planning condition within the original planning approval.

2 - The property does not enjoy any PD rights until the approved scheme has been implemented.  Therefore you cannot really submit a Planning application or a Certificate of Lawful Development until such time a physical property exists on the site and you have legally implemented the previous Planning Approval.

Many Councils have formulated their own interpretation of when this point is (i.e. when the dwelling actually exists and is capable of receiving further applications for PD or Planning).  I have heard cases from one extreme to another.  One Local Planning Authority insisted to a client that it should be finished and occupied for 2 years whilst another felt that the installation of the foundations was enough to have implemented the approval & physical dwelling.  Therefore you need to check with your particular Planning Dept. what their threshold is for the confirmed 'birth date' of your new property AND GET IT IN WRITING!!

Our interpretation of the formal 'birth point' of a new dwelling for adding Permitted Development extensions (and a certificate of lawful development application) is when the 'majority' of the framework of the building has been installed (i.e. - all of its volume). 

I would also go further & suggest that you make sure that it is water tight and most importantly you have discharged ALL of the Planning Conditions required prior to development taking place on the site.  If you do not do this you leave yourself wide open to the Council suggesting that the scheme has not yet been fully implemented due to the non-compliance of the Conditions and,  as such, you have illegal building works until such times the Conditions are complied with - trust me - it has happened before!

3 - If you combine the schemes (new house & extension works) you have technically not built or implemented what you have received Planning Permission for.  You are then forced to either remove the offending extension or submit a fresh Planning Application for the larger dwelling house all over again which you really want to avoid at all costs as it could be refused and at appeal with the eventual removal being the only option.

Therefore, you MUST NOT combine the construction works at all even if it costs you more to do so.  One MUST follow the other - new dwelling then the extension.

SO WHAT ARE THE ALTERNATIVES TO THIS PRAGMATIC APPROACH?

It is realised that the economics of two separate build schemes may not make sense and the added costs and time scales may put the project out of reach so is there another way of securing a safe method of building the extended dwelling?

There is only one option really and that is to submit a second Planning application for the extended dwelling before you start on site.  The revised Planning application should make it quite clear that the scheme is an 'alternative' to the previous planning approval and that the only difference is for the modest extension that will comply with the requirements for Permitted Development.  Your Design & Access statement should also make it clear that the extension will be added irrespective of the outcome of the revised Planning Application by implementing it as a PD extension later on if need be.

You should make it clear that the benefit of this revised planning approach is purely for the neighbours which will reduce the impact of the works on site to a shorter time scale and the disruption to them would be extended by the Permitted Development route.  This may or may not be considered by the Planners or the Committee as a material fact but the neighbours may see the benefit of this approach and not complain.

However, there are technicalities with this approach as well.  Now that the Planners are having to endorse your PD extension scheme through the formal planning permission route, it MUST also now comply with the Councils Design Guides & Planning Policies.  Therefore if your PD extension scheme interferes with the lines of light from the neighbours windows for example, the Planners will not be able to approve the extended dwelling even though you could build it later under Permitted Development.  Therefore, if you do go down this second planning application route you must make sure that the PD extension element is fully compliant with the Councils Planning Policy and design Guides.

Good luck!