Loft Conversion Planning Permission
Will my loft conversion need planning permission?
Most loft conversions are carried out as permitted development. This means you do not require planning permission as long as the new loft rooms meet some basic rules on maximum size and height.
If you have a detached or semi-detached house you can extend you space by 50m3 or if you have a terraced house, you can go up to 40m3.
Materials should be similar in appearance to the existing house.
Dormers should be set back at least 200mm from the eaves.
No balconies, verandas or raised platforms including roof windows with fold out balconies.
Side facing windows should be obscure-glazed and non- opening unless the parts that can be opened are more than 1.7m above the floor in the room.
I summary your loft conversion should be OK without planning permission unless:
You raise the height of the main roof, or build a new dormer higher than the ridge of the existing roof.
You construct a new dormer window on a roof facing a highway.
You increase the volume of your house by more than 50m3 for detached and semi-detached or 40m3 for terraced properties.
Your property is Listed or in a Conservation Area
If you discover that you do need planning permission, you’ll have to ﬁll in a planning application form, pay a one-off fee and send off three copies of the form and three copies of the existing layout, the proposed layout, the existing elevations, the proposed elevations, the location plan and the site plan.