Do I Need Planning Permission for Bifold Doors?

If you are replacing an existing set of patio, French or sliding doors with bifolds, in the same opening, on a house, you are almost certainly within permitted development and no planning application is needed.

Most of the questions we get asked about bifolds are not really planning questions at all. They are structural questions wearing a planning hat, because the thing homeowners usually want is not a like-for-like swap — it is a wider opening than the one they have.

A door-for-door replacement in an existing aperture is treated the same way as a replacement window. Permitted development rights under the GPDO cover alterations to a dwellinghouse, and a new door set in an existing opening sits comfortably inside them.

The usual caveats apply. Permitted development rights can be removed by a condition on the original planning permission — very common on estates built since the 1990s — or by an Article 4 direction over the area. Both are worth checking before you order.

Bifolds are bought for the view, so in practice most installations involve taking out a section of the rear wall to make the aperture wider. On the planning side this is usually still permitted development on a rear elevation. On the building side it is a different matter entirely.

Removing load-bearing masonry means a new structural opening, which needs a correctly sized and supported lintel or steel beam, with the loads above properly carried down. This is regulated under Part A of the Building Regulations and it is notifiable work.

If the bifolds are going into a new single-storey rear extension, the planning question belongs to the extension, not the doors. Single-storey rear extensions on a house can fall under permitted development within defined depth, height and coverage limits, with a prior approval route available for deeper ones under the larger home extension scheme.

Those limits are tighter on designated land, which includes conservation areas and National Landscapes. If you are extending rather than replacing, check the extension's position first and treat the doors as a detail of it.

Separately from any structural work, the door set has to meet the same standards as any replacement glazing:

Four situations, and they are absolute rather than a matter of degree.

Find your local planning authority — across the area we cover that will be West Oxfordshire, Cherwell, Oxford City, Vale of White Horse, South Oxfordshire, Cotswold District, Cheltenham Borough, Wiltshire Council, Swindon Borough or West Berkshire. Search their planning map for conservation area boundaries and Article 4 directions, check Historic England's National Heritage List for listed status, and read the conditions on your own property's original permission through the council's planning portal.

If you want certainty in writing before spending money, a Lawful Development Certificate confirms the work is permitted development. It costs a fraction of a full application and is worth it on a borderline case.

We survey before we quote, and that survey includes the structural position, not just the measurements. If your opening needs widening we will say so, tell you that it brings building control into the job, and be clear about what sits inside our scope and what does not. Our glazing work is self-certified under Assure and you receive a Building Regulations Compliance Certificate for it.

This guide covers homes in England and is general information rather than formal advice. Rules differ in Wales, Scotland and Northern Ireland, and individual properties carry their own conditions, directions and covenants. Your local planning authority and building control body are the final word.