Is planning permission required?


Planning Permission for Loft Conversions

Planning Permission for Loft Conversions in London, Middlesex & Hertfordshire is not usually required for most properties providing your property meets a certain criteria.  

The majority of properties in London & the home Counties have automatic planning permission for certain alterations which is commonly referred to  as Permitted Development.  

A loft conversion for your house is considered to be permitted development, not requiring an application for planning permission, subject to the following limits and conditions:

  • A volume allowance of 40 cubic meters additional roof space for terraced houses*
  • A volume allowance of 50 cubic meters additional roof space for detached and semi-detached houses*
  • No extension beyond the plane of the existing roof slope of the principal elevation that fronts the highway
  • No extension to be higher than the highest part of the roof
  • Materials to be similar in appearance to the existing house
  • No verandas, balconies or raised platforms
  • Side-facing windows to be obscure-glazed; any opening to be 1.7m above the floor
  • Roof extensions not to be permitted development in designated areas**
  • Roof extensions, apart from hip to gable ones, to be set back, as far as practicable, at least 20cm from the original eaves
  • The roof enlargement cannot overhang the outer face of the wall of the original house.

If your property exceeds any of the criteria above or is a flat then limits then planning permission will be required.

Please note that even if Planning Permission is not required Building Regulations Permission will still be required so a full set of working drawings is still necessary for most alterations.

These drawings will be required by both your local authority Building Control Department and by your building team to use during construction.

We can provide a full set of both architectural drawings and/or building control drawings for all properties.

Please get in touch for a no obligation quotation for this service.

ONLINE SALE - Book architectural drawingsdoff

sale, on-site celebrity, or other event? Be sure to announce it so everybody knows and gets excited about it.

Display their FAQs

Customers have questions, you have answers. Display the most frequently asked questions, so everybody benefits.