If you are looking to replace your old or timber windows with options such as UPVC windows or aluminium windows, you might have questions about the relevant regulations. In some instances, planning permission is required for windows. But there are also strict building regulations relating to glazing, and you must always adhere to them.

If you’re simply replacing windows in a similar size and style currently on the house, planning permission is not necessary. If your plan is to add new windows, a planning application may be required. Let’s look at some more detailed information about what falls into permitted development and what doesn’t.

Windows: Key Considerations

You do not normally need to apply for planning permission to replace doors or windows with something of a similar appearance. Building regulation approval is required for all glazing replacement work, however, or you can use a registered installer.

There are certain circumstances where you do need planning permission:

  1. You are fitting a skylight that protrudes over 150mm beyond the roof slope’s plane.
  2. The intended skylight protrudes higher than the highest point of the roof.
  3. You are fitting an upper-floor side elevation window that isn’t obscure-glazed and can be opened (unless, in the case of an openable window, the opening portion is more than 1.7 metres from the room’s floor).

If you live in a listed building, designated area or anything that falls under an Article 4 Directive, you may need planning permission for any glazing work.

Do Bay Windows Require Planning Permission?

Bay windows are a different prospect from standard windows. They protrude outwards from the wall of your property, so they are often treated like an extension for planning permission purposes. Here are the key considerations:

Building Regulations for New Windows

Planning permission decides whether or not you will be allowed to build or alter an existing structure. Building regulations exist to control the quality of building work and dictate how structures can be built for safety reasons.

You are always required to comply with building regulations for windows. The main areas that need to be covered are:

If you don’t want to have to seek approval for building regulations yourself, you can work with a registered installer with prior approval to carry out window replacement work.

Other Important Building Regulations Relating to Windows

There have been recent additions to building regulations that impact window installation in various ways.

Building Regulations Part O: Reducing Overheating

This addition to building regulations came into effect in June 2022 in response to changing priorities concerning climate change, thermal efficiency and thermal performance. As part of an effort to reduce emissions, this regulation is aimed at reducing overheating by:

Part O: Relating to Glazed Areas of New Builds

Windows and glazed areas are limited to a maximum size depending on:

High-risk areas must incorporate external shading. Internal blinds/curtains and tree foliage are not adequate for this.


Part F: Replacement Windows in Existing Buildings

If the windows being replaced have background ventilators, the replacement windows should have vents of at least equal size. If there are no background ventilators in the windows being replaced, it must be demonstrated that ventilation will not be made worse when the windows are replaced. It may be necessary to introduce background ventilators in the new windows.

In some cases, it could be considered that a trickle vent will reduce the energy efficiency of a window. But this is addressed by the fact that trickle vents can be closed to make the window frame draught-proof.

Vents are important to enable air to circulate in a room, removing moisture from the air. This limits condensation, which could otherwise contribute to issues like mould and dampness.

Is Planning Permission Required to Paint Windows?

If you want to paint your windows in order to change their colour, you do not need planning permission or building regulations. However, some properties may impose restrictions on changes you make to the external appearance. For example, listed buildings or leasehold properties may not permit this.

Restrictions to Look Out for Before Painting or Replacing Windows

Here are some things to be mindful of before starting any work on windows:

Leasehold: Leasehold properties, like apartments and new builds, may have covenants in place that restrict your choice of colour and style for windows. Contact the management company before you initiate any work.

Why choose Eco Thermal Design for your new windows?

Eco Thermal Design has transformed countless homes across Barnsley, Sheffield and other areas of South Yorkshire. We are experts when it comes to windows and can help you find the right windows for your home. Our expert team can help you decide on the right window for your home, and our team of fitters can complete their work to the highest standards, causing you minimal disruption along the way. We’re proud of the quality of our products, work and people, which is echoed by our customers in our Which Trusted Trader reviews.

If you would like to speak to one of our window experts or get a quote, you can contact us here or give us a call on 0800 009 6241.

What Our Customers Say

“Quality products are only as good as the team that fit them and in our case both the product and the fitters resulted in a first class and professional installation. Respectful of our home and tidied up at the end of each day….Thank You”
Les Finucane

“Excellent service from Eco Thermal again. Would recommend to anyone. Also good to have a local firm that you can trust.”
Ross Duguid

“Very happy with the whole process and of course the finished installation.”
Michael Senior

You can also read our reviews on Which Trusted Trader where we are rated five stars.