Listed Buildings by Area: England's Complete Data (2026)

The Grading System

Listed buildings in England are graded by Historic England according to their architectural or historic significance. The grade determines the level of scrutiny any proposed changes will receive:

The vast majority of listed buildings are Grade II. This is the grade most homeowners encounter when extending or altering their property. While Grade II listing adds significant constraints and cost, sensitive extensions are regularly approved - particularly rear extensions that don't affect the principal elevation.

Grade I and Grade II* buildings face much stricter scrutiny. Extensions to these buildings are rare and typically require involvement from Historic England as a statutory consultee. Most alterations to Grade I buildings are limited to essential maintenance and repair.

Listed Buildings by London Borough

We queried planning.data.gov.uk to count listed buildings across London boroughs. The concentration in central and west London is striking, with Westminster alone containing more listed buildings than many entire counties.

The pattern is clear: boroughs with pre-Victorian and Georgian building stock have the highest concentrations. Westminster's count of 3,455 reflects centuries of institutional, ecclesiastical, and high-status residential building. At the other end, Barking & Dagenham's 48 listed buildings reflect a housing stock dominated by 1920s-1950s council estates.

For homeowners, the practical question is simple: is your specific property listed? Even in boroughs with thousands of listed buildings, the vast majority of homes are unlisted. The listing applies to individual buildings (and sometimes groups), not to areas. Being near a listed building does not restrict your own property, though being in a conservation area does.

How Listing Affects Extensions

Listed building consent is a separate process from planning permission. You may need both. Here's what listing means in practice for extension projects:

• 1.No permitted development rights. Listed buildings have no PD rights for extensions. Every external alteration - including replacing windows, adding a porch, or building a rear extension - requires listed building consent. Internal alterations that affect character (removing walls, altering staircases, changing fireplaces) also need consent.
• 2.Specialist architect required. Conservation officers expect designs that demonstrate understanding of the building's significance. Architects experienced in heritage work know how to present a case that balances modern living requirements with preservation. Expect architectural fees 20-40% higher than for unlisted work.
• 3.Heritage materials add 30-50% to build costs. Conservation officers often require traditional materials: lime mortar instead of cement, handmade bricks, natural slate, timber sash windows. These materials cost more and require specialist tradespeople. A rear extension in London stock brick with lime mortar pointing can cost £3,000-5,000 more than modern cavity wall construction.
• 4.Heritage Impact Assessment. Most listed building applications require a Heritage Impact Assessment (sometimes called a Heritage Statement). This document, typically prepared by your architect or a heritage consultant, describes the building's significance and assesses the impact of your proposals. Cost: £1,000-3,000.
• 5.Longer timelines. Listed building consent applications take 8 weeks (the same statutory target as planning), but Grade I and II* applications are referred to Historic England, which adds 21 days for their consultation response. Pre-application advice is strongly recommended for listed buildings.

The Listed Building Consent Process

Listed building consent runs in parallel with (not instead of) planning permission. For an extension to a listed building, you typically need both. Here's the process:

Listed building consent has no application fee - it is free to apply. However, the preparation costs (heritage assessment, specialist drawings, consultant fees) mean the overall process is more expensive than a standard planning application.

Carrying out works to a listed building without consent is a criminal offence. Unlike planning enforcement (which is discretionary), listed building enforcement is mandatory. Councils must prosecute unauthorised works, and owners can face unlimited fines and even imprisonment. This is one area where cutting corners carries serious legal risk.

What Gets Approved?

Despite the constraints, extensions to listed buildings are regularly approved. The key is demonstrating that your proposal preserves or enhances the building's significance. Approaches that tend to succeed:

• -Rear extensions with contemporary design. Conservation officers often prefer a clear distinction between old and new. A modern glass-and-steel rear extension that is clearly of its time, rather than a pastiche of the original, can be easier to approve than an imitation period extension.
• -Basement extensions. Where the ground conditions allow it, basement extensions can add significant space without altering the external appearance. This approach is common in Westminster and Kensington & Chelsea.
• -Restoring original features. Applications that include restoration of lost original features (reinstating sash windows, reopening blocked fireplaces, removing inappropriate modern additions) alongside new work are viewed more favourably.
• -Subordinate additions. Extensions that are subordinate to the original building - lower in height, set back from the principal elevation, and smaller in footprint - are more likely to be accepted.

The Cost Premium

Extending a listed building typically costs 30-50% more than an equivalent extension to an unlisted property. Here's where the additional costs come from:

For a typical 15m² rear extension in London, the listed building premium translates to an additional £20,000-40,000 on top of the standard cost. A 15m² extension that would cost £85,000-120,000 on an unlisted property could cost £110,000-170,000 on a listed building.

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