Planning Permission for Windows

The good news for most homeowners is that swapping old windows for new ones of a similar appearance is usually treated as “permitted development” and does not require a planning application. But planning is only half the story: separate building regulations apply to the energy performance and safety of the new windows, whatever the planning position. Understanding the difference between the two saves confusion and delay.

When you usually do not need planning permission

For a typical house outside any special designation, replacing windows like-for-like — similar style, similar appearance, in the same openings — normally falls under permitted development. That covers most upgrades from tired single glazing to modern double-glazed units. You are free to change frame colour and material in most cases, provided the overall look is not dramatically different from the original.

When you probably do need it

• Conservation areas and where an Article 4 direction applies — permitted development rights may be removed, so even a like-for-like change can need consent. See our conservation area window rules.
• Listed buildings — window work almost always needs listed building consent.
• Flats and maisonettes — permitted development for windows generally does not apply, and your lease may require the freeholder’s consent instead.
• New or enlarged openings — creating a new window, or making one much bigger, can need permission, especially where it affects a neighbour’s privacy.

Building regulations and certification

Whether or not planning permission is needed, replacement windows must meet building regulations for energy efficiency, ventilation, safety glass and, in some rooms, means of escape. The simplest route is to use an installer registered with a competent-person scheme such as FENSA or Certass, who self-certifies the work and registers it with the local authority. You will receive a certificate — keep it safe, as buyers’ solicitors ask for it. A good installer will explain what happens on installation day and how the certification is handled.

Timing and funding

If your project does need consent, factor the approval time into your plans, then check the typical lead times for the fitting itself. Surveyors covering many areas have appointments this month.

Compare routes on our window funding by property type hub, or return to the Fund Your Windows homepage.