Loft conversion planning permission

And permitted development rights concerning attic conversions

Whilst you must always check before you start any work, Loft conversion planning permission is not always required. There were changes in planning laws that were introduced in October 2008 to remove thousands of projects from the planning process, many more attics can now be converted without it.

Permitted development

loft conversion planning permission

Certain alterations to a properties original size are generally allowed under these permitted development rights;

  • If you have a terraced house, you can increase the roof volume by 40 cubic metres. This must be kept below the original ridge line.
  • If you have a detached or semi-detached property, you can increase the volume of the roof by up to 50 cubic metres.
  • If your property fronts a road/highway, you cannot extend beyond the plane of the existing roof pitch. (That means no dormers, usually only velux windows are allowed).
  • Extension must be kept below the highest part (ridge) of the roof
  • You must use materials that match those of the existing house.
  • Raised platforms, balconies and verandas are not allowed.
  • Windows that are side opening must have obscure glass and be installed 170cm from finished floor level (your building inspector may let you lower the height if you install a guard rail inside).
  • Certain designated areas are excluded from permitted development rights.
  • Apart from hip to gable examples, extensions need to be set back at least 200mm from the eaves or as far as is reasonably possible.
  • Exceptions

    If you live in a world Heritage Site, national park, area of outstanding natural beauty or on the suffolk or norfolk broads then permitted development rights will likely be reduced or taken away.

    I built a small pitched roof dormer window on the back of my house that didn't require planning permission at the time because it fell within permitted development.. I hope!

    Shortly after I converted my loft, the road I live in was made part of a conservation area. This now means I have to get planning permission to alter anything on the front of the property, even the colour of my front door.

    I would never have obtained planning approval for the velux windows on the front of my property had it already been a conservation area or listed building, as the idea is to preserve the original appearance of the street and properties for historical reasons. I might also have needed planning permission for the dormer at the back.

    Obtaining loft conversion planning permission

    If you have checked with your local authority and it turns out you do need permission, there are several things you need in order to apply;

  • Site location plan
  • Block plan
  • Design and access statement (not always needed)
  • The site location plan and block plan you need to be ordnance survey maps and they're a rip off. I was annoyed when I had to buy mine getting planning permission for a new front door because it's a lot of money for a drawing. It's not like the council don't know where your bloody house is! (Photocopy them in case you need them again in future).

    The design and access statement outlines how you have considered various external factors when designing your proposal like disabled access, elderly/young persons use of the area.

    Get in touch with your local council and find out exactly what's needed as early as possible, you'll be lucky to get planning permission within 6 weeks! I used a surveyor I knew to do all my drawings and to finalise and submit my application to the local council. Whilst I had to pay £300, it saved me the hasstle of re-applying if I got it wrong because he knew the people in the office and what they would/wouldn't accept.

    * As always, the information on this page about Loft conversion planning permission is intended as a guide only. Always consult your local planning department for advice and never start a conversion or any other building project until you have the permission you need in writing.

    With or without planing permission, loft building regulations are different. They govern the minimum standards that must be met when building a loft conversion and must always be met.

    Loft conversion planning permission related pages

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    Image courtesy of Suat Eman)

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