A pergola is an open-sided structure, typically consisting of vertical posts supporting an open lattice or beam roof, used as a garden feature to support climbing plants or provide a shaded outdoor seating area. For planning purposes, a pergola is generally treated as an outbuilding and in most cases can be built without planning permission.

When a Pergola Is Permitted Development

A free-standing pergola in the garden of a dwellinghouse is an outbuilding and is subject to the Class E permitted development rules. The standard conditions require that it is within the curtilage of the house and not forward of the principal elevation, does not exceed 2.5 metres in eaves height, does not exceed four metres in overall height with a dual-pitched roof or three metres with any other roof type, and does not take the total outbuilding and extension coverage above 50 percent of the curtilage excluding the house footprint.

Most residential pergolas, which are typically lightweight open structures, easily meet these conditions. An open pergola with no solid roof falls even more clearly within permitted development because its open structure means it is less likely to be considered a building in the planning sense at all.

Attached Pergolas

A pergola attached to the house and used as a covered outdoor area adjacent to the rear or side of the dwelling may be treated as an extension rather than a free-standing outbuilding. If the pergola structure connects to the house wall and is large enough to be considered a material change to the building, the extension permitted development rules rather than the outbuilding rules would apply. In practice, an open pergola attached to the house but without solid walls or a solid roof is unlikely to be considered a building for Building Regulations purposes and is of low planning risk in most cases.

Conservation Areas and Listed Buildings

In conservation areas, outbuildings that would be visible from a highway may require planning permission even if they would be permitted development elsewhere. For listed buildings, any structure within the curtilage requires listed building consent and potentially planning permission. Checking with the local planning authority before constructing a pergola at a conservation area or listed property is advisable.

Building Regulations

A simple free-standing pergola with no walls, no enclosed roof, and no electrical installations is generally exempt from Building Regulations as it is not a building in the regulatory sense. If a solid roof, enclosed sides, or electrical installations are added, the structure may cross the threshold into Building Regulations territory depending on size and enclosure.

Summary

Most residential pergolas are permitted development and do not require planning permission, as they fall within the outbuilding size and height limits and do not constitute enclosed buildings. Front garden placement, conservation areas, listed buildings, and very large structures may trigger planning requirements. Building Regulations do not apply to basic open pergola structures but do apply to any electrical installations.