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I’m replacing a window, do I need planning permission or building control approval increase its size?
Increasing the size of a window will often fall under permitted development rights, meaning an application for planning permission is not required to make the change, provided limits and conditions are met.
Any new window must be of similar appearance to the original which you are replacing.
Permitted development rights do not apply to flats. To increase the size of a window in a flat or maisonette you will require planning permission.
If you live in a listed building, you will require listed building consent for any major changes.
Where the work has as significant impact on the external appearance of the house, especially on the principal elevation, planning permission may be required.
Building control approval will likely be required where the change impacts the structure of a building, this primarily occurs when an opening Is widened. When altering walls you may want to consult a structural engineer.
Building control will also consider energy efficiency, glazing, ventilation and fire safety.
Common Questions
Rules governing outbuildings apply to sheds, playhouses, greenhouses and garages as well as other ancillary garden buildings such as swimming pools, ponds, sauna cabins, kennels, enclosures (including tennis courts) and many other kinds of structures for a purpose incidental to the enjoyment of the dwellinghouse.
If you are unsure if your planned building falls into the category of 'outbuildings' or if you are unsure if planning permission is required, please contact your local planning authority.
Outbuildings are considered to be permitted development, not needing planning permission, subject certain limits and conditions.
A ‘P certificate’ may refer to confirmation that electrical installations within a building are compliant with Approved Document P of the building regulations.
An electrician who is Part P certified is able to self-certify domestic work they complete, meaning you do not have to submit a building notice. To ensure your electrician is Part P certified, use a registered competent person.
A single storey rear extension can fall under permitted development, meaning planning permission may not be required providing it meets certain criteria.
In terms of height, the extension must:
- Be no taller than four metres at its highest point
- Have eaves no higher than the eaves of the original house
- Not exceed the height of the original dwelling
Read about planning permission for extensions on Planning Portal
Approved Documents are official guides that explain how to comply with the building regulations. Published by the government, each document provides practical guidance on meeting the requirements of a specific ‘Part’ of the regulations. They cover a wide range of building work, including plumbing, electrical installations, extensions and ventilation.
The latest versions of the Approved Documents, which support the technical ‘Parts’ of the building regulations, along with Regulation 7, are available on Planning Portal.
Demolishing and building a new lean-to will still have comply with planning requirements.
If you live in a conservation area or listed building you may require approval for the demolition.
Whether a lean-to requires planning permission will depend on what the lean-to is used for, it may be an extension, pergola, carport, conservatory or gazebo.
In some cases a building a lean-to will be classified as permitted development, meaning an application for planning permission is not required provided specified limits and conditions are met. If these are exceeded, then you must apply for planning permission.
Permitted development rules vary based on the type of work you are completing, visit our interactive house mini guides for details on the specific rules.
If you live in a listed building, you will need listed building consent for any significant changes.
