This is general guidance based on standard permitted development rights in England. Rules differ for listed buildings, conservation areas, and properties with Article 4 directions. Always confirm with your local planning authority before starting work.
Do I Need Planning Permission for a New Window Openings?
Creating new window openings in existing walls where none previously existed. This is generally permitted but side-facing windows at upper-floor level have specific restrictions to protect neighbours' privacy.
The General Position
Whether you need planning permission depends on the specific details of your project, your property type, and your location. Check the conditions below carefully.
Adding new windows to existing walls is generally permitted under Part 1, Class A, provided the windows do not overlook neighbouring properties. Side-facing upper-floor windows must be obscure glazed and non-opening below 1.7m from the floor. New windows in the front elevation may change the building's appearance and could need PP in some areas.
Conditions and Requirements
- 1Side-facing windows at upper-floor level must be obscure glazed and non-opening below 1.7m from the floor
- 2New windows should not significantly alter the external appearance of the dwelling
- 3Must comply with Building Regulations (structural, thermal, safety glazing)
- 4Check if the property has any Article 4 directions restricting window changes
Size and Dimension Limits
- No specific PD size limits for individual windows
- Structural lintel and support requirements apply based on wall type and opening size
When Permitted Development Does Not Apply
- Listed buildings require listed building consent
- Conservation areas may restrict new openings on visible elevations
- Overlooking is the most common reason for neighbours to object
- Creating large new openings in structural walls requires Building Regulations approval
What About Building Regulations?
Building Regulations approval is required covering structural support (lintels, padstones), thermal performance of the new window (Part L), safety glazing in critical locations (Part K), security requirements (Part Q, PAS 24), and ventilation (Part F). A structural engineer may be needed for large openings in load-bearing walls.
Building regulations are separate from planning permission. You may need both, one, or neither depending on your project. Building regulations cover the safety and quality of building work, including structural integrity, fire safety, insulation, ventilation, and drainage.
How to Apply for Planning Permission
Check if you need permission
Review the permitted development rules above. If in doubt, contact your council or apply for a Lawful Development Certificate.
Prepare your application
You will need scaled drawings, a site plan, and a completed application form. An architect or planning consultant can help with this.
Submit to your local council
Applications can be submitted online via the Planning Portal or directly to your council. Select your council below for a direct link.
Wait for a decision
8 weeks for householder planning applications if PP is needed..
Application cost: £258.
What Happens If I Build Without Permission?
Moderate risk if the new window overlooks a neighbouring property without being obscure glazed where required. The council can require the window to be altered or blocked up. This is a common source of neighbour disputes and enforcement complaints.
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Select Your Council
Choose your local council for guidance specific to your area, including links to apply and whether your council has conservation areas or Article 4 directions that could affect your project.
London
South East
South West
East of England
East Midlands
West Midlands
North East
North West
Yorkshire and the Humber
CA = has conservation areas. A4 = has Article 4 directions. These may restrict your permitted development rights.