Do You Need Planning Permission for New Windows?

Key Findings

• Most standard window replacements fall under permitted development rights, meaning you don’t need planning permission
• If your property is in a conservation area or is a listed building, you will likely need consent before making any window changes
• Building regulations compliance is mandatory for all window installations, even when planning permission isn’t needed
• Buckinghamshire has over 200 conservation areas where window replacement rules are stricter than in standard residential zones
• The Residence Collection offers conservation-friendly uPVC windows that replicate timber aesthetics while meeting planning requirements

Have you been putting off replacing those draughty old windows because you’re worried about getting tangled in planning red tape? You’re not alone. At Premier Windows, we’ve helped thousands of Buckinghamshire homeowners navigate the often confusing world of planning permission for windows.

The good news is that in many cases, you won’t need to apply for planning permission at all. But there are important exceptions you should know about, especially in a county like ours with so many protected historic areas.

Let’s clear up the confusion and help you understand exactly when you need permission for your new windows and when you don’t.

When Don’t You Need Planning Permission for Windows?

For most homeowners, replacing windows is straightforward from a planning perspective. Under permitted development rights, you can usually replace existing windows without seeking permission, provided:

• The new windows are similar in appearance to those being replaced
• You’re not creating any new window openings
• Your property isn’t listed or in a conservation area
• You’re not changing a window to a door (or vice versa)

This means that for standard replacement projects where you’re simply swapping old windows for new ones of a similar style, you typically won’t need to submit a planning application.

In Buckinghamshire, where we fit hundreds of window replacements each year, most of our installations in regular residential areas proceed without any planning hurdles.

When Do You Need Planning Permission for Windows?

There are several scenarios where planning permission becomes necessary:

Creating New Window Openings

If you’re planning to add a completely new window where there wasn’t one before, you’ll usually need planning permission. This is because you’re altering the external appearance of your property in a significant way.

For example, if you want to add a new window on the side of your house that faces your neighbour, planning permission will almost certainly be required.

Material Changes in Appearance

Even when replacing existing windows, if the change in appearance is substantial, you might need permission. This could include:

• Switching from traditional wooden frames to uPVC in certain areas
• Changing the style dramatically (e.g., from casement to bay windows)
• Altering the size, shape, or position of window openings

Conservation Areas

Buckinghamshire is blessed with beautiful historic towns and villages, many of which are designated conservation areas. If your home is within one of these areas (like parts of Aylesbury, Amersham, or Wendover), even like-for-like window replacements might require planning permission.

Conservation areas have special protections to preserve their character, and window styles are often crucial to maintaining this character. We always advise our customers in these areas to check with their local planning authority before proceeding.

Buckinghamshire is home to over 200 conservation areas.

Listed Buildings

If you own a listed building, you’ll need listed building consent for practically any changes to windows, even if it’s just replacing them with identical designs. This applies regardless of where in the building the windows are located.

Buckinghamshire has thousands of listed buildings, and we’ve worked sensitively on many of them to install appropriate windows that meet both conservation requirements and modern performance standards.

Flats and Maisonettes

Unlike houses, flats and maisonettes don’t benefit from the same permitted development rights. If you live in a flat, you’ll generally need planning permission for any window replacements that alter the appearance of the building.

Building Regulations vs. Planning Permission

An important distinction to understand is that building regulations approval is not the same as planning permission. Even if you don’t need planning permission, you’ll still need to comply with building regulations.

Building regulations focus on technical standards rather than appearance, covering aspects like:

• Energy efficiency (U-values)
• Safety glazing
• Means of escape in case of fire
• Ventilation

At Premier Windows, all our installations comply with current building regulations, and we provide the necessary certification. In most cases, our status as an Assure-registered company means we can self-certify compliance, saving you the hassle of applying to building control.

Local Rules in Buckinghamshire

Local planning policies can sometimes introduce additional restrictions beyond national guidelines. In Buckinghamshire’s different council areas, there may be specific policies regarding:

• Window materials in certain streets or neighbourhoods
• Colour restrictions in some areas
• Design guidelines for properties of particular ages or styles

For example, in parts of Amersham Old Town or in villages within the Chilterns (an Area of Outstanding Natural Beauty), there are often stricter guidelines about window appearances, even for non-listed buildings.

Special Cases: Bay Windows and Dormers

Bay Windows

Adding a new bay window will almost always require planning permission as it extends beyond the original footprint of your house. Replacing an existing bay window with a similar design usually falls under permitted development, but significant changes in size or style will need permission.

Roof Windows and Dormers

Adding roof windows or dormers is subject to specific permitted development conditions:

• They must not protrude more than 150mm from the roof slope
• They must not be higher than the highest part of the roof
• Side-facing windows must have obscured glazing and be non-opening if less than 1.7 metres from the floor of the room

How to Check If You Need Permission

If you’re unsure whether your window project needs planning permission, here are some practical steps:

1. Check the Planning Portal – The UK Planning Portal website offers guidance on permitted development rights.
2. Contact Your Local Planning Authority – Buckinghamshire Council can provide advice specific to your property.
3. Apply for a Lawful Development Certificate – This confirms your project doesn’t need planning permission, giving you peace of mind.
4. Talk to Experienced Installers – At Premier Windows, we’ve worked on properties throughout Buckinghamshire and can often advise on likely planning requirements based on your location and property type.

The Conservation Solution: Residence Collection

For properties in conservation areas across Buckinghamshire, we’re proud to offer the Residence Collection – a range of uPVC windows that perfectly replicate the appearance of traditional timber frames. These innovative windows provide:

• Authentic timber aesthetics with traditional joinery details
• Period-appropriate designs suitable for conservation areas
• Modern thermal performance (far superior to original timber windows)
• Low maintenance requirements

The Residence Collection has been specifically designed to meet the stringent requirements of conservation officers, providing a solution that preserves heritage character while delivering modern performance. In many cases, these windows can be installed in conservation areas without planning permission as they maintain the original character so effectively – though we always recommend checking with your local authority first.

The Residence Collection combines a traditional appearance with modern benefits.

Our Approach at Premier Windows

We understand that navigating planning rules can be daunting. That’s why we offer comprehensive support throughout the process, from initial design to installation.

For properties in Buckinghamshire’s conservation areas or listed buildings, we work closely with local conservation officers to ensure our window designs meet both your needs and the planning requirements.

Our team is experienced in producing detailed drawings and specifications for planning applications, and we can advise on the most appropriate window styles for your property’s age and character.

Whether you’re in Aylesbury, High Wycombe, or one of the many beautiful villages across the county, we’re here to help you get the windows you want without falling foul of planning regulations.

If you’re considering new windows and are unsure about the planning implications, give us a call on 01296 422 842. We’d be happy to provide our expert advice based on your specific situation.