One of the first questions we get asked about any loft conversion is whether it needs planning permission. The honest answer is: it depends — but most loft conversions in London do not.
Permitted Development Rights
Under Permitted Development, most homeowners can convert their loft without full planning permission, provided the work stays within certain limits — typically an additional roof space volume of 40 cubic metres for terraced houses and 50 cubic metres for detached and semi-detached houses.
When You Will Need Planning Permission
You will usually need full planning permission if your property is a flat or maisonette, if it sits within a conservation area, if the extension would exceed the volume allowances above, or if any part of the new roof would face onto a highway.
Building Regulations Still Apply
Even where planning permission is not required, every loft conversion must still comply with Building Regulations covering structural strength, fire safety, insulation, and staircase access. This is a separate approval from planning permission and is not optional.
Our Approach
Before we quote any loft conversion, we carry out a permitted development assessment as standard. If planning permission is needed, we handle the application on your behalf and factor the realistic timeline into your project schedule from day one.
