The majority of plots are sold with planning permission already secured whether that be outline planning permission or detailed planning permission for a specific house design.

Quite often, self-builders like the look of a plot, but not the house permitted on it. Here we answer some of the most common questions about changing the existing planning permission and the best way to go about it.

Why do sellers go to the trouble of obtaining detailed permission?

A plot owner could have secured the value of their plot just by obtaining outline planning permission, however, often detailed planning permission is essential, for example, when the plot is within a conservation area, or for a replacement dwelling.

Obtaining detailed planning permission can show potential buyers the scale of house that can be accommodated on the plot, or show that issues such as overlooking of neighbours, proximity to trees, or an awkward access can be addressed.

It’s worth looking at the council’s planning records, especially the planning officer’s report. It may highlight any issues that may arise should you wish to change the existing planning permission.

Can I change the existing planning permission?

Having detailed planning permission on a plot for a specific house doesn’t mean you can’t apply for something completely different, but if you want to change the permitted design significantly, a new planning application will need to be submitted.

It is possible to make minor changes after receiving planning permission that do not require a new planning application and there are a number of options for this;

Non-material amendments

In general terms, non-material amendments are very minor changes that do not materially alter the size and scale of the development and don’t affect the neighbouring properties.A ‘non-material amendment’ might be one where:
– It is a very small change.
– It does not vary significantly from what was described on the planning permission.
– It does not conflict with any conditions on the permission.
– It does not breach planning policy.
– It does not significantly move the external envelope
– It does not increase the height of the roof.
– It does not introduce or move windows or other openings that could affect other properties

The benefit of this approach against a new planning application is that the statutory consultations (such as notice letters to your neighbours) that are undertaken in the planning process are not required for the amendment. The views of others have already been taken into account, and therefore the final decision can be made by the planning officer alone in a shorter period of time.

You can apply using a standard form on the Planning Portal website and you can include more than one change on the same application.

Minor material amendments

Minor material amendments are changes that are more significant than the ‘non-material’ amendments and are described as being changes whose scale and nature results in a development which is not substantially different from the one which has been approved. This might include changes where:
– The site boundary is not changed
– The siting, landscape, scale and height is not significantly changed
– The use is not changed.
– The appearance is not adversely affected.
– The change is compliant with local planning policy and with the conditions attached to the original permission.
– Changes to windows or other openings that do not impact on neighbouring properties.
– The interests of parties consulted about the original application are not disadvantaged.

Changes will still need to be minor. They may include changes to the building that result in small reductions. Being to its scale, height or footprint. But still not alter the description of the development or the red edged area of the application. Changes need to be wholly acceptable, uncontroversial and be of limited impact. Slight increases to the footprint or scale of buildings may be acceptable under this process but only where there is no impact upon neighbouring properties.

Changes that significantly alter the existing scheme

If your proposed changes fundamentally or substantially alter the substance of your approved scheme, you will need to submit a fresh application. Whilst the principle of development has already been established, this new submission will still be determined on its merits and considered against any other changes that may have taken place since the original permission was granted, such as shifts in local or national policy.Significant changes may include:
– Changing the size of the permitted design
– Increasing the size is one of the most common reasons for wanting to change planning permission.
– The main concern with increasing the size of a house is whether a larger house will fit on the plot. Consider whether it would then fit in with its neighbours.

Quite often, the key to getting approval for an increase in size is to do so without increasing the height. Including the bulk of the building. There are a number of clever ways to achieve this, for example having hipped roofs. Another is lowering the ridge line. Thus reducing the roof pitch and adjusting the levels of the building help to keep a low profile.

What is important is that your replacement design will be no more prominent than the original.

Changing the design

It is possible to change the design of a house that already has planning permission. However planning officers become stuck to a particular design and are unwilling to see it change. This is quite often the case when the planning officer has been closely involved in the design process. Especially if they influenced it through pre-application discussions. This is particularly common in Conservation Areas.

A planning officer wedded to a particular design may need reminding of the Government advice. Contained in Planning Policy Statement No. 1, says: Local planning authorities should not attempt to impose architectural styles or particular tastes and they should not stifle innovation, originality or initiative through unsubstantiated requirements to conform to certain development forms or styles.

A good alternative design and quality drawings will be key to success where a change of design is required.

Further information on planning permission.