Please note only a few basic allowences are included below and those are subject to additional rules so please check with us or your local Planning Authority

• Additions and alterations made to a roof to enlarge a house (eg a loft conversion or the replacement of an existing flat roof with a pitched roof) will only be permitted development if no part of the house once enlarged exceeds the height of the highest part of the roof of the existing house.  If it does, planning permission will be required
• Dormer windows as part of a loft conversion, or any other enlargement of the roof space, are not permitted development on a principal elevation that fronts a highway and will therefore require an application for planning permission.   Roof-lights in a loft conversion on a principal elevation may however be permitted development as long as they meet the requirements set out under Class C .
• To be permitted development any additional roof space created must not increase the volume of the original roof space of the house by more than 40 cubic metres for terraced houses and 50 cubic metres for semi-detached and detached houses.   Any previous enlargement to the original roof space in any part of the house must be included in this volume allowance
• Alterations to the roof of a house for loft conversions involving the creation of balconies are not permitted development and will require planning permission.   A balcony is defined as a platform with a rail, ballustrade or parapet projecting outside an upper storey of a building.   A ‘Juliet’ balcony, where there is no platform and therefore no external access, would be permitted development.   A raised platform is any platform with a height greater than 300 millimetres and would include roof terraces