Class AA Prior Approval Granted for an Additional Storey in West Mersea
Class AA prior approval for the addition of a single storey to a bungalow in Essex, effectively doubling the dwelling's living space under the new permitted development right introduced in August 2020.
PRIOR APPROVAL SUCCESSESCOLCHESTERESSEX
Andrew Ransome
7/3/20262 min read
In 2021, I secured prior approval from Colchester City Council under Class AA of the General Permitted Development Order for the vertical extension of an existing bungalow in West Mersea, Essex — adding a complete upper storey and effectively doubling the amount of living space within the property.
The case used a relatively new permitted development right introduced in August 2020, demonstrating all relevant eligibility criteria and the structural capacity of the existing building to support the additional floor.
Prior Approval Vertical Extension in Colchester
Class AA prior approval was obtained for the addition of a single storey to an existing bungalow in West Mersea, Essex. The approval effectively doubled the amount of living space at the property, transforming a single-storey home into a full two-storey dwelling — a significant increase in accommodation achieved without a conventional planning application.
Class AA of the General Permitted Development Order came into force in August 2020, providing homeowners and landlords with a new route to add space to existing houses by extending upwards.
For detached houses of two or more storeys, up to two additional storeys may be added, subject to a maximum height increase of seven metres.
For single-storey bungalows — as in this case — only one additional storey is permitted, and the height increase must not exceed 3.5 metres.
Class AA operates through a prior approval process rather than a full planning application.
The local planning authority can only consider specified matters: the design and external appearance of the proposed additional storey; the impact on the amenity of neighbouring premises; and transport and highway matters.
As with all Class AA cases, it was important to establish that the existing bungalow structure was capable of supporting the proposed additional floor.
Colchester City Council granted approval.
Planning Application Advice
If you are considering adding a storey to your home and want to understand whether Class AA permitted development rights apply, I can advise on eligibility and manage the prior approval process. Contact me to discuss your project.
Andrew Ransome MRTPI - Email: andrew@andrewransome.co.uk
About me
Andrew Ransome is a Planning Director and a Chartered Member of the Royal Town Planning Institute (RTPI), with more than two decades of experience in town planning.
He specialises in delivering strategic planning solutions for complex developments across both rural and urban environments, helping clients navigate planning challenges and unlock development opportunities. Connect with Andrew on Linkedin.
Prior Approval Successes
Prior Approval Information
Get in touch for planning advice: Email: andrew@andrewransome.co.uk
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