How to make a windows planning application

If you need planning permission or listed building consent, follow our guidance documents. 

This will help prevent a delay to your application or it getting refused.

Replace windows so they match the originals

To protect the character of the building, replacement windows should match the originals': 

  • appearance
  • detailing
  • opening type

Particularly when windows share the same design across a group of buildings or flats.

For listed buildings and those in conservation areas, you must accurately reproduce the originals. If you do not, it's likely that permission will be refused.

Meet thermal insulation standards

Replacement windows need to meet thermal insulation standards set out in building regulations.

To meet these standards new windows will usually need to be double glazed. But there are exemptions from the building regulations on heritage assets. This is to make sure new work does not harm the special interest of the building.

Follow window design

As a general rule replacement windows should:

  • fit neatly into existing openings, recessed into the established reveal depth
  • avoid stick-on or non-integral glazing bars as they can loosen and fall off.

On heritage assets replacement windows should:

  • avoid visually obvious trickle-vents
  • be of the same material as the original windows.

The Planning Portal also has guidance on planning and building regulations. 

Provide scale drawing requirements

Provide drawings of the original and proposed windows so that we can compare them.

Listed buildings and properties in Article 4 Direction areas

Provide 1:20 scale elevations and larger scale 1:5 or 1:2 detailed cross sections.

Cross sections should show how the window unit sits within the window reveal and relates to the existing sill.

For sash windows, section drawings should include:

  • top rail (including sash box)
  • glazing bar
  • meeting rail (of both sashes)
  • bottom rail
  • sill (including sash box)

If your building is listed, you'll also need to provide:

Make a planning application