Windows & doors in Westminster: Planning Permission Guide
A guide to replacing windows and doors in Westminster — when you need planning permission and typical costs.
The City of Westminster has the densest concentration of conservation areas and listed buildings in the UK, covering almost the entire borough. Article 4 Directions layer on top of this in many areas, restricting virtually any external alteration. Listed building consent is required frequently in addition to planning permission. The council's design expectations are among the most stringent in the country — professional planning advice is essential.
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5 nearest comparables & refusal reasons for your address.
Get my report — £9See a sample →Recent windows & doors decisions in Westminster
The 5 most recent decided applications. Addresses redacted to postcode area.
Erection of staircase enclosure at roof level, replacement of windows, installation roof terrace railings and decking.
Replacement of non-original sashes to windows at 1st, 2nd and 3rd floor rear and 3rd floor front with Fineo slim glazing, retaining sash …
Installation of external condenser units to the rear, including internal and external alterations at ground and lower ground floor, inclu…
Replacement windows at lower ground floor level.
Replacement of all existing timber-framed sashes to both front and rear elevations with double-glazed timber sashes, including replacemen…
These are borough-wide. See the 5 nearest to your address.
Get my report — £9Permitted Development Rules
Replacing or adding windows/doors may need planning permission in conservation areas or for listed buildings.
Replacing windows and doors like-for-like generally doesn't need planning permission. However, in conservation areas or listed buildings, changes to the appearance of windows and doors may require consent.
Typical Costs in London
Window and door costs depend on the number of openings, material choice, and style.
Typical total
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Highly variable depending on number of windows, material (UPVC vs timber vs aluminium), and style. Per-window costs typically £500–£1,500.
Get a personalised cost estimate based on your actual windows & doors dimensions.
Get my estimateWhich Professionals Do You Need?
Window replacements rarely need professional services. Suppliers typically handle measurement, manufacture, and installation.
This project is unlikely to need specialist professional services beyond a competent builder.
This type of project does not typically require architectural services.
This guidance is based on a typical semi-detached house with no special constraints. Listed buildings, conservation areas, and attached properties may require additional professional input.
Find out exactly which professionals you need for your windows & doors.
Get personalised guidanceConservation Areas & Listed Buildings
In conservation areas, changing window materials (e.g. timber to UPVC) or styles may need planning permission. Listed buildings always need Listed Building Consent for any window or door changes.
Properties in conservation areas often have reduced permitted development rights. Some project types (like side extensions) lose PD rights entirely. An Article 4 Direction can remove additional PD rights.
Listed buildings (Grade I, II*, or II) have no permitted development rights at all. Any external alteration requires Listed Building Consent in addition to any planning permission. An architect experienced in heritage work is essential.
Check if your property is in a conservation area or has other planning constraints.
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