Doors and Windows Planning Permission in England & Wales

Planning permission is not normally required for repairing, fitting or replacing doors and windows (including double glazing).

However, if the building is listed or is in a conservation area (or other designated area) you should consult with your local planning authority. You can find your local planning authority at the UK Government’s online planning resource for England & Wales.

Also, if you are a leaseholder, you may first need to get permission from your landlord or management company.

Building Regulations

Since April 1, 2002, building regulations have applied to all replacement glazing. The regulations apply to thermal performance and other areas such as safety, air supply, means of escape and ventilation.

An external window or door is a controlled fitting under the Building Regulations and as a result of this classification these Regulations set out certain standards to be met when such a window or door is replaced.

You should use an installer registered with a Competent Person Scheme (BSI, CERTASS or FENSA). A registered installer will be approved to carry out the work to comply with Building Regulations without involving local authority building control. Once the work is complete you will receive a certificate showing the work was done by a registered installer. More information about Competent Person Schemes can be found on the Communities & Local Government website.

Alternatively, you could use an unregistered installer or DIY. In which case approval can be sought from the relevant Building Control Body, either at your local authority or an approved inspector. They will check the replacement window(s) or door(s) for compliance and, if satisfied, issue a certificate of compliance.

Thermal Heat Loss

Dwellings are required to be energy efficient. A method of achieving greater energy efficiency is to take steps to reduce the amount of heat that is lost through the glazing in both windows and doors.

If you are to install windows and doors you should be aware that they need to comply with the requirements of the Building Regulations in relation to the amount of heat that can to pass through the glass and framework, which is measured as a U-Value. This U-Value should not be exceeded. For information on the maximum U-Value allowed please refer to Approved Document L-1B, Table 2. For any window that is provided as part of an extension/loft conversion refer to list (a). For an existing dwelling, any replaced or new window, refer to list (b).

Safety glazing

Safety glazing should be provided to any glass in a critical area. Below is a list giving general view as to when safety glazing is required:

Any glazed area within a window below 800mm from floor level
Any glazed area within a window that is 300mm or less from a door and up to 1500mm from floor level
Within any glazed door up to 1500mm from floor level
See diagram 1 in Approved Document N for more information.


Windows and doors provide ventilation to rooms within a dwelling and rules apply to how much ventilation. The type and extent of ventilation will be dependent on the use and size of the room. For example, rooms where steam will be produced (kitchens, bathrooms, utility rooms etc) should be provided with higher levels of ventilation (normally mechanical fans and windows) than other rooms where suitably sized window openings and background (trickle) ventilators may suffice.

Fire Safety

There are two aspects to be considered:

1. Fire spread between properties through unprotected areas
2. Means of escape in case of fire

Unprotected areas

External doors and windows may need to have fire resistance and (in the case of doors) be self-closing or (in the case of windows) be fixed shut to limit the risk of fire spread between adjacent properties. The area of walls, doors and windows permitted to have reduced or undetermined fire resistance (known as unprotected areas) will be dependant on how close these elements are to the boundary.

Means of escape

When replacing any window, the opening should be sized to provide at least the same potential for escape as the window it replaces. If the original window that is being replaced was larger than necessary for the purpose of escape, then the new window opening could be reduced down to the minimum as specified in the criteria below.

The means of escape should be considered for any new window installed to an extension or existing dwelling. If an escape window is required then criteria set out below should be followed. It is also generally good practice to replace any window on the first floor that is not used as an escape window with an escape window.

See below for the general criteria for egress windows:

Width and Height: Either of these are not to be any less than 450mm
Clear Openable Area: No less than 0.33m
Cill height: No less than 800mm and no more than 1100mm from floor level
Only one window per room is generally required.

Access to buildings

When replacing main entrance doors in a dwelling unit that has been constructed since 1999, it is important to ensure that the threshold remains level, otherwise the works will not comply with the Building Regulations. This is because it would be making the threshold worse than it was when constructed. This is to enable a wheelchair user to have continued access to the dwelling.

Useful websites

Planning Portal: UK Government’s online planning resource for England & Wales.
BSI: British Standards Institution
CERTASS: one of the original Quality Mark certification bodies
FENSA: the leading body providing homeowner protection in the double glazing industry.
Communities & Local Government website


This is an introductory guide and is not a definitive source of legal information.

Planning Information

If you are in any doubt you should contact your local planning authority before undertaking any work.

Building Regulations

The Building Regulations content on this page provides you with a practical level of guidance to enable you to better understand how the Building Regulations might impact on a building project you are doing or considering.

This is not a definitive interpretation of the Building Regulations. Unless you have a reasonable working knowledge of building construction it would be advisable before any work is started to obtain appropriate professional advice which is relevant to the building work you want to carry out (e.g. from an architect, a structural engineer, a building surveyor, a heating engineer or replacement window specialist) and to choose a registered builder, or a registered installer, to carry out the work.

This guidance relates to the planning regime for England. Policy in Wales may differ. If in doubt contact your Local Planning Authority.