Quick answer for most UK homes
If you own a house and you are repairing, maintaining, or replacing windows like for like, you do not usually need planning permission. Planning Portal guidance for England says you do not usually need permission for repairs and minor improvements, inserting new windows and doors of a similar appearance to those used in the construction of the house, and internal secondary glazing.
In England, permission can be needed if your council has removed permitted development rights using an Article 4 Direction, if your home is in a designated area such as a conservation area, or if the building is listed and needs listed building consent.
| What you want to do | Planning permission is usually needed | Why this matters |
|---|---|---|
| Replace an existing window on a typical house with something similar in overall look | Usually no | Commonly covered by permitted development, but local restrictions can still apply |
| Create a new window opening or significantly change size | Sometimes | More likely to affect the external appearance and structure, especially on principal elevations |
| Add a new upper floor side window | Sometimes | Rules on privacy apply, including obscure glazing and opening restrictions in England guidance |
| Work on a listed building | Very often yes | Listed building consent is commonly required for significant works and is separate from planning permission |
| Home is in a conservation area or subject to Article 4 Direction | Sometimes yes | Permitted development rights may be restricted or removed, so you must check with the council |
| Flat or maisonette, not a house | More likely | Planning rules differ and councils can interpret policies differently |
When you do not usually need planning permission?
For most homeowners asking about windows planning, the low risk scenarios are the ones where the character and outward appearance of the home stays broadly the same.
For houses in England, you do not usually need to apply for planning permission for repairs, maintenance, and minor improvements, and for inserting new windows and doors that are of a similar appearance to those used in the construction of the house.
If you are adding internal secondary glazing, you do not usually need planning permission.
If you are increasing the size of a window in a house, it will often fall under permitted development rights, provided limits and conditions are met and the new window is of similar appearance to the original.
For Wales, the Welsh Government position is also direct: planning permission is not normally required for repairing, fitting or replacing doors and windows, including double glazing, with the important caveat that listed buildings and conservation areas need local authority input.
A key practical point: even where planning permission is not usually required, national rules can be affected by additional local rules, and you should check before starting work.
When you might need planning permission for a new window?
This is where the search term “planning permission for new window” matters. The moment you move away from like for like replacement, you need to pause and check the details.
In England, if you are inserting new windows, the guidance commonly focuses on whether the new window is of similar appearance and on privacy controls for certain locations. If new windows are in an upper floor side elevation, they must be obscure glazed and either non opening or the opening part must be more than 1.7 metres above the floor level.
Creating a new opening for a new window will often not require planning permission when the new windows look similar to those previously used in the house, with the same privacy rules for upper floor side elevations.
Bay windows are a common exception because they can project outward. A new bay window is treated as an extension and may require permission.
You should also treat these situations as higher risk for planning permission:
If your home is in a conservation area or another designated area, there may be additional restrictions and you are strongly advised to check with your local planning authority before carrying out work.
If your council has made an Article 4 Direction withdrawing permitted development rights, you may need to apply for planning permission even for work that would normally be permitted.
If you live in a listed building, you will generally need listed building consent for significant works, and it should be treated as a separate requirement from planning permission.
If you live in a flat or maisonette, the planning regime differs from houses. you may need planning permission to fit new windows in a flat, but you should not usually need permission for identical like for like replacements, and local policy varies council to council.
If you are a leaseholder, you may first need permission from your landlord, freeholder, or management company.
If you are unsure, a lawful development certificate can provide formal confirmation. The UK government planning guidance explains that where development is permitted under national permitted development rights, you can apply for a certificate of lawful development to receive formal confirmation.
Planning permission is not the same as building regulations
For England, building regulations have applied to all replacement glazing since 1 April 2002 and that the regulations cover areas such as thermal performance, safety, air supply, means of escape, and ventilation. It also describes external windows and doors as controlled fittings under the Building Regulations.
You can use an installer registered with the relevant competent person scheme, and the registered installer can carry out work to comply with building regulations without involving local authority building control, with a certificate provided when the work is complete.
If you use an unregistered installer or do it yourself, approval can be sought from a building control body who will check compliance and issue a certificate if satisfied.
For window replacements and glazed doors, if the contractor is registered with one of the relevant competent person schemes, you would not need to make a building regulations application.
Ventilation changes are often overlooked in window upgrades. Government guidance confirms Approved Document F volumes came into force on 15 June 2022. FENSA guidance for homeowners states that changes to Approved Document F require the majority of replacement windows and doors to be fitted with trickle vents.
If your project is a structural alteration such as widening or creating a new opening, building control approval is likely to be required where a change impacts the structure, such as when an opening is widened.
How to check your home and move forward
Where Idealcombi fits in: if you are planning a replacement window or planning permission for a new window opening, the easiest way to reduce risk is to start with a specification that meets building performance requirements and respects the look of the property. Idealcombi windows are available with double or triple glazing, with triple glazed windows achieving reference U values of 0.74 W/m²K. You can upload plans to get a free window quote, which can help you cost compliant options before you commit.
Planning Permission FAQs
You do not usually need planning permission for inserting new windows and doors that are of a similar appearance to those used in the construction of the house. You should still check if you are in a designated area, if the property is listed, or if an Article 4 Direction removes permitted development rights, as Planning Portal flags these as situations where extra controls can apply.
Often, no, but it depends on location and design. Inserting new windows that look similar to those previously used in the house will often not require planning permission, but privacy rules apply for upper floor side elevations.
If you are adding a bay window to the front, this would require planning permission because it is classed as a forward extension. If you are unsure, a lawful development certificate can provide formal confirmation.
In England, you need to take privacy rules seriously for upper floor side elevations. If new windows are in an upper floor side elevation, they must be obscure glazed and either non opening or have the opening part more than 1.7 metres above the floor level. For flats, permitted development allowances described for houses do not apply, and planning permission may be required depending on the change.
This usually sits under the same general idea as doors and windows alterations: it may be permitted development for a house if it is a similar appearance and not restricted by local controls, but you must check the specifics. The addition of a new external doorway will often fall under permitted development rights where the new doors are of similar appearance to those used elsewhere on the original building, and permission may be required for listed buildings, conservation areas, or where an Article 4 Direction applies.
Even if planning permission is not required, building regulations are crucial here because you are creating or widening a structural opening. New external doorways that create a new or widened opening must comply with building regulations and a new structural opening will require a building regulations application
French doors are usually treated as external doors. If you are replacing doors in an existing opening on a typical house, planning permission is often not required, but if you are creating a new opening or changing the front elevation, you should check with the local authority, especially in conservation areas or if an Article 4 Direction applies. As with any glazed door replacement, building regulations will apply to performance, safety glazing, and ventilation.
Planning regime for flats and maisonettes differs from houses and you may need planning permission to fit new windows, especially if the appearance or size changes. It also says you should contact your local planning authority because local policy varies. It also highlights that if your flat is in a listed building, you are very likely to need listed building consent and doing works affecting the special historic character of a listed building without consent is a criminal offence.