Planning Permission for a Hip to Gable Loft Conversion
Some hip to gable loft conversions can be completed under permitted development rights, but the property, location and previous alterations all need to be considered.
Permitted Development Volume Limits
Permitted development normally allows up to 40 cubic metres of additional roof space for terraced houses and 50 cubic metres for semi-detached and detached houses.
Previous enlargements to the original roof count towards this allowance. If an earlier owner added a dormer, for example, the volume created may reduce the amount available for a future conversion.
This is particularly important with a hip to gable and rear dormer loft conversion, as the combined extensions can use a substantial proportion of the available allowance.
Read more about permitted development for loft conversions.
The Eaves Set-Back Rule
Roof enlargements under permitted development are normally required to sit at least 0.2 metres back from the original eaves, measured along the roof plane.
However, hip to gable enlargements are specifically excluded from this requirement. This means the new gable can extend to the eaves line, even though a rear dormer constructed alongside it will generally still need to comply with the relevant set-back rule.
Conservation Areas
Permitted development rights for roof extensions are restricted on designated land, including conservation areas.
This is particularly relevant in South London, where parts of Clapham, Battersea, Dulwich, Brixton and Streatham are within conservation areas. Individual streets may also be affected by Article 4 directions or local design policies.
We assess the planning position before recommending a design so you understand what is achievable before progressing with detailed drawings.
Read our guide to loft conversions in conservation areas.