22 Westminster Road: A Planning Feasibility Walkthrough for 2026

If you are researching a property extension, a loft conversion, or a potential purchase, you have probably found yourself typing an address into a search bar and hoping something useful comes back. 22 Westminster Road is a good example of the kind of ordinary residential property that raises exactly the questions most UK homeowners and developers actually need answered: not "what is permitted development" in the abstract, but "given this specific house, on this specific plot, what can I realistically build, how long will it take, and what will it cost?"

This guide takes that practical angle. Rather than repeating the rulebook on permitted development rights, it walks through the process you should follow when assessing a property like 22 Westminster Road for extension or development potential in 2026, including the council process, realistic timescales, indicative costs, and the mistakes that trip up even experienced developers.

Why a Single Address Is a Useful Case Study

Every planning assessment starts in the same place: a specific plot, a specific building, and a specific set of designations that apply to that piece of land. Two houses that look identical from the street can have completely different development rights if one sits inside a conservation area and the other does not, or if one was built in 1965 and the other in 2015.

Using a single address such as 22 Westminster Road as a working example forces you to go through the same steps a planning consultant would use on a real instruction: establish the facts about the site, audit what already exists on the plot, work out which permitted development routes are actually open, and then map out the council process from first enquiry to decision notice. That is the structure this article follows.

Step 1: Establish the Planning Status of the Site

Before you sketch a single extension, you need to answer a handful of factual questions about the property. For a house such as 22 Westminster Road, these should include:

• Is the property inside a conservation area, National Park, Area of Outstanding Natural Beauty, the Broads, or a World Heritage Site? Collectively these are known as article 2(3) land, and they carry materially tighter restrictions than a standard suburban plot.
• Is the building listed, or does it sit within the curtilage of a listed building? Listed status removes most permitted development rights entirely and triggers listed building consent requirements for almost any change.
• Has an article 4 direction removed specific permitted development rights in this street or area, regardless of conservation area status?
• When was the house originally built? This single fact determines whether certain routes, such as upward extensions, are even available.
• What has already been built on the plot, and by whom? Previous extensions, garages, sheds and outbuildings all count towards later calculations.

You can check most of this through the council's interactive planning map (usually found on the local planning authority's website), the Historic England listing search, and the council's own conservation area register. For a property like 22 Westminster Road, this desk-based check should take an afternoon and costs nothing beyond your time, but skipping it is the single most common reason self-build and extension projects stall midway through design work.

Step 2: Audit What's Already on the Plot

Once you know the designation status, the next job is a curtilage audit. This matters because permitted development for extensions is not simply about the size of the new build; it is about the cumulative footprint of everything on the plot.

Under the relevant permitted development rules, if the total ground area covered by buildings within the curtilage (excluding the original house itself) would exceed 50% of the curtilage as a result of new work, the development is not permitted under permitted development rights and a full planning application becomes necessary. Crucially, this calculation includes every existing garage, shed, summerhouse and outbuilding on the plot, even ones erected decades before the current owner bought the property. Only the footprint of the original house itself is excluded.

For a semi-detached or terraced property like 22 Westminster Road with a modest garden, this 50% ceiling can be reached surprisingly quickly, particularly if a previous owner has already added a single-storey rear extension, a detached garden office, and a garden shed. Before commissioning drawings, measure the plot and every existing structure on it, then calculate the running total against the curtilage area. This five-minute sum can save weeks of abortive design work later.

Step 3: Decide Which Direction to Extend

With the designation checks and curtilage audit complete, you can start thinking about where an extension could actually go.

Front extensions: almost always ruled out

Under permitted development, an extension is not allowed if it would project beyond a wall that forms the principal elevation of the original house, or beyond a side elevation that fronts a highway. The rule is applied generously against the homeowner: it covers not just the wall itself but the area in front of an imaginary line drawn from the end of that wall out to the property boundary. On a corner plot, where a side wall also fronts a road, there is a further restriction on side extensions. In practice, this means that for the vast majority of houses, including a street-fronting property such as 22 Westminster Road, any extension towards the front of the house will need a full planning application rather than relying on permitted development.

Side and rear extensions: depends heavily on conservation area status

If the property is not on article 2(3) land, single-storey rear extensions and side extensions have reasonably generous permitted development allowances, subject to the usual height, depth and curtilage limits.

If 22 Westminster Road (or any similarly situated house) sits within a conservation area, National Park, AONB or World Heritage Site, the position changes significantly:

• Side extensions of any kind are not permitted development at all; a planning application is required.
• Rear extensions are restricted to a single storey under permitted development; anything with more than one storey to the rear needs planning permission.
• Cladding the exterior in stone, artificial stone, pebble-dash, render, timber, plastic or tiles is not permitted development, so re-facing or refreshing the exterior of the house also requires an application if the property is on article 2(3) land.

This is one of the most common surprises for homeowners who assume permitted development rights are uniform across the country. They are not, and the conservation area check in Step 1 is what determines which of these two very different rulebooks applies to your project.

Loft conversions and roof extensions

A loft conversion is often the cheapest way to add a bedroom or bathroom without touching the footprint of the house, but the rules narrow considerably in sensitive areas. Roof balconies are never permitted development anywhere, so any design incorporating a Juliet balcony or roof terrace at loft level will need planning permission regardless of location. More significantly, if the property is on article 2(3) land, roof extensions and dormers are not permitted development at all, me