Batcheller Monkhouse Chartered Town Planners have the experience and knowledge to advise and guide clients through the Planning system. Offices covering Kent, Sussex, Surrey and Hampshire.

Our Tunbridge Wells Planning Team working alongside Mike Bliss Architect have secured another upward extension to a dwelling in Tandridge District Council, utilising permitted development (PD) rights granted under Class AA of Part 1, Schedule 2 of the GDPO.

The usual PD rights available to householders for extensions such as rear and side extensions require that they are built from walls which formed the ‘original dwellinghouse’. In practice this means the dwelling as it was originally built (or as it was on 1 July 1948 if built before this date). This can present a problem if the building has already been significantly enlarged in the past and there is a limited amount of the original building left to extend from. Often there will be no option but to apply for full planning permission, which comes with higher cost, delay and greater scope for the Local Authority to reject the proposal.

The beauty of Class AA is that it allows you to erect up to two storeys (subject to meeting certain criteria) above the ‘Principal part of the dwellinghouse’. This is defined as the main part of the dwelling, excluding any elements of the property which are of a lower ridge height. The nuance of this wording, opens up huge opportunity as it allows you to build upon previously extended elements of a dwelling as long as they have continued a consistent ridge height throughout the property.

Such an opportunity presented itself with this project allowing us to achieve an extension above previous side and front extensions. The cumulative effect of these extensions has been to double the floor area of the ‘original dwellinghouse’ with the Class AA extension accounting for 50% of this increase. It is also worth remembering that Class AA is unaffected by wider planning designations such as Green Belt so for those finding it difficult to secure alterations to their homes in these areas, the legislation can offer another solution.

If you would like advice on maximising the opportunities available to you under permitted development rights on your property, please do not hesitate to get in contact with Nicholas Webb in our Tunbridge Wells Planning Team by telephone: 01892 509280 or by email:

Offices in BattleHaywards HeathPulborough and Tunbridge Wells.