Windows Planning Permission FAQ’s

Yes — understanding the planning and regulatory requirements before proceeding is an important early step in any window replacement project, and it is something Hinson Custom Made takes seriously. 

We have extensive experience working with properties across the full range of situations — from standard domestic permitted development through to listed buildings and conservation area properties — and can advise you on what approvals are likely to be needed based on your property type and location. In many cases, a brief conversation or a review of your property details will allow us to give you a clear picture before you commit to anything. 

We work regularly with local conservation officers and planning authorities and are familiar with the requirements and sensitivities of different areas. Getting the planning and regulatory position clear at the outset avoids expensive surprises later.   

A standard householder planning application has a statutory determination period of eight weeks, within which the local planning authority is required to issue a decision. In practice, applications for straightforward like-for-like replacements in conservation areas are often processed within this timeframe, though some authorities are slower. 

Listed building consent applications have the same eight-week statutory period. Complex applications or those requiring consultation with Historic England may take longer. Pre-application advice — where you contact the planning authority informally before submitting to discuss the proposal — can significantly improve the chances of a smooth application by identifying concerns early. Hinson Custom Made can assist with the preparation and submission of planning applications and has experience managing the process for clients with heritage properties.

If your window replacement or alteration does require planning permission, the application is submitted to your local planning authority, usually via the Planning Portal. A householder planning application is the standard route for most domestic window changes and typically requires: a completed application form; a site location plan and existing/proposed drawings (elevations showing the current and proposed windows); photographs of the existing windows; and the relevant fee (currently £258 for a householder application in England).

In conservation areas or listed building applications, a heritage statement explaining why the proposed works are appropriate may also be required. Many applicants engage an architect or a specialist company like Hinson Custom Made to prepare the drawings and supporting documentation, which increases the likelihood of a successful outcome.

In conservation areas and listed buildings, the local authority’s primary concern is preserving the historic character and appearance of the built environment, and this significantly influences which window materials are acceptable. Timber windows are the traditional and most widely accepted material in heritage contexts — correctly detailed and painted or stained, timber replicates the original appearance most faithfully. 

Aluminium-clad timber windows are also acceptable in many cases, offering the appearance of timber externally with improved durability. Slim-profile aluminium windows can be approved in some conservation area contexts, particularly for more modern-era listed buildings or in situations where the existing windows were already metal. PVC-U (UPVC) windows are almost never approved in listed buildings and are frequently objected to in conservation areas due to their distinctly modern appearance. 

Hinson Custom Made produces bespoke timber windows to heritage specifications, purpose-built for sensitive contexts.

FENSA — the Fenestration Self-Assessment Scheme — is the competent person scheme established to allow window and door installers to self-certify that their installations comply with building regulations in England and Wales. An installer registered with FENSA can issue a FENSA certificate confirming that the replacement windows or doors installed meet building regulations for thermal performance, safety glazing, and ventilation without the need for a separate building control inspection. 

The FENSA certificate is an important document: it provides legal proof of building regulations compliance and is required by solicitors during a property sale to confirm that any window replacements were carried out legally. Without a FENSA certificate or equivalent, a homeowner may face delays in selling their property or be required to obtain a retrospective inspection. Hinson Custom Made is FENSA registered and issues certificates with every installation.

Replacement windows are subject to building regulations approval even when no planning permission is required. The relevant regulations cover thermal performance (U-values), safety glazing in critical locations such as low-level panels and near doors, ventilation (replacement windows must provide adequate background ventilation, usually via trickle vents), and structural integrity. 

To demonstrate compliance, replacement windows must either be installed by a company registered with a competent person scheme (such as FENSA or CERTASS), which allows them to self-certify compliance and issue a certificate without involving the local authority, or the work must be inspected and approved by the local building control office. Hinson Custom Made is registered with the appropriate competent person schemes and issues certificates on completion of every installation, giving homeowners the documentation they need. 

Changing the size or design of windows moves beyond a like-for-like replacement and is more likely to require planning permission. Creating a new window opening in a wall, significantly enlarging an existing window, or adding windows on a side elevation that overlooks a neighbouring property are all changes that may require a planning application under permitted development rules. Similarly, changing from sash windows to casement windows — or vice versa — may be considered a material change in appearance in certain areas. 

The threshold at which changes become ‘material’ is a matter of judgement for the local planning authority, and what is acceptable in one area may not be in another. If you are considering anything beyond a straight replacement of an existing window to a similar design, Hinson Custom Made would always recommend checking with the local planning authority or your local planning department before ordering.

Conservation areas do not automatically require planning permission for window replacement, but they do apply additional restrictions compared to unrestricted residential areas. In many conservation areas, permitted development rights are removed or restricted by an Article 4 Direction, which means that works that would normally be permitted — including replacing windows — require a planning application. 

Even where permitted development rights do apply in a conservation area, the appearance requirement is stronger: the replacement windows must not be materially different in appearance from those they replace, and local authorities will often object to the introduction of modern materials (such as PVC) where traditional materials were used originally. If you are in a conservation area, always check with your local planning authority or consult Hinson Custom Made before proceeding — the rules vary by area and incorrect assumptions can create problems further down the line.

Yes — listed buildings require listed building consent for any alterations that affect the character of the building, and this almost always includes changes to windows. Listed building consent is a separate and additional process to standard planning permission and is assessed by the local authority’s conservation officer. The key consideration is whether proposed works preserve or enhance the character of the listed building and are in keeping with its historic integrity. 

For listed properties, this typically means replacing windows with historically accurate replicas in the same material — most commonly timber — and to the same profile, glazing bar configuration, and design as the originals. PVC windows are almost never approved for listed buildings. Hinson Custom Made specialises in bespoke timber windows made to heritage specifications, and regularly works with conservation officers and homeowners on listed building projects.

In most standard residential situations, replacing windows with like-for-like products does not require planning permission, as it falls under permitted development rights. Permitted development allows homeowners to make certain alterations to their property — including replacing windows — without needing to apply to the local planning authority, provided the new windows are of a similar appearance to those being replaced and the property is not subject to any additional planning restrictions. 

However, there are important exceptions: properties in conservation areas, listed buildings, national parks, and some areas of outstanding natural beauty (AONBs) may have conditions that restrict or require approval for changes to windows, even like-for-like replacements. Hinson Custom Made has extensive experience with permitted development and planning requirements and can advise on what is needed for your specific property.