Heritage significance and harm: how planning decisions are made

 

Heritage significance and harm are at the centre of planning decisions affecting listed buildings, conservation areas, scheduled monuments, registered parks and gardens, World Heritage Sites and other heritage assets. The key question is not simply whether a proposal changes an old building or can be seen from one. It is what makes the heritage asset significant, how the proposal affects that significance, and what weight the law and planning policy require that effect to receive.

The rules changed materially when the August 2026 National Planning Policy Framework was published. The familiar policy label “less than substantial harm” no longer appears in the current NPPF. Instead, policies HE5 to HE7 distinguish between a positive effect, no effect, harm, substantial harm and total loss, with different balancing rules for designated and non-designated heritage assets.

This page explains the current framework in England, including the statutory duties for listed buildings and conservation areas, how significance should be assessed, what substantial harm now means, how public benefits enter the balance, and why even relatively limited heritage harm cannot simply be treated as an ordinary planning objection.

If you are preparing the supporting evidence for an application, see our guide to Heritage Impact Assessments, which explains what HE5 expects the submitted assessment to contain.

 

What does heritage significance mean?

 

The NPPF glossary defines significance as the value of a heritage asset to this and future generations because of its heritage interest. That interest may be archaeological, architectural, artistic or historic.

Significance is not limited to the fabric you can touch. It can derive from the physical presence of the asset, its design, materials, archaeology, historical associations and the contribution made by its setting. This is why development some distance from a listed building can still affect its significance, while a physically close proposal may sometimes cause no heritage harm at all.

The starting point should therefore be an explanation of why the asset matters. A long description of a building’s age and appearance is not necessarily a significance assessment. The useful questions are which features, relationships, views, spaces, fabric or historical associations contribute to the asset’s heritage interest, how important each contribution is, and which of those things the proposal would actually affect.

For a non-designated heritage asset, the same basic exercise is needed even though the later policy balance is different.

 

Start with the statutory duties, not just the NPPF

 

The NPPF is extremely important, but it does not replace the statutory duties in the Planning (Listed Buildings and Conservation Areas) Act 1990. The August 2026 Framework expressly says those obligations remain in place.

There are three duties which frequently matter:

• Listed building consent: section 16(2) requires the decision-maker to have special regard to the desirability of preserving the listed building, its setting and features of special architectural or historic interest
• Planning permission affecting a listed building or its setting: section 66(1) requires special regard to the desirability of preserving the building, its setting and its special features
• Planning functions concerning land or buildings in a conservation area: section 72(1) requires special attention to the desirability of preserving or enhancing the character or appearance of the area

These duties sit alongside the ordinary rule in section 38(6) and the development plan. A proposal cannot lawfully be assessed by reading a local heritage policy in isolation and forgetting the statutory protection Parliament has given to listed buildings and conservation areas.

The courts have treated “preserving” in this context as meaning doing no harm. The leading authority is South Lakeland District Council v Secretary of State for the Environment [1992] 2 AC 141. Preservation does not require a proposal to enhance an asset, but once harm is identified the statutory duty affects the weight that harm receives in the planning balance.

 

How HE5 assesses the effect of development

 

Policy HE5 of the August 2026 NPPF provides a much clearer sequence than the older Framework. A proposal affecting a heritage asset should first be accompanied by a proportionate assessment of the asset’s significance, including any contribution made by its setting. The assessment should then identify the effect of the proposal as one of the following:

• positive effect, where significance would be enhanced or better revealed
• no effect on significance
• harm to significance
• substantial harm, where the proposal would seriously affect a key element of the asset’s significance
• total loss of significance

HE5 makes another important point: it is the effect on significance, not the physical scale of the development, that matters. A small alteration can cause serious heritage harm if it removes or damages something central to significance. Conversely, a large development is not automatically substantially harmful simply because it is large.

This is the discipline a good planning statement or heritage statement should follow. Identify significance first, identify the affected element second, explain the change third, and only then classify the effect.

 

The 2026 NPPF no longer uses “less than substantial harm”

 

This is probably the most important change for anyone used to the previous NPPF.

Older versions divided harmful effects on designated heritage assets into substantial harm and less than substantial harm. The August 2026 Framework has removed the latter expression from the policy test. HE5 now uses the simpler category harm, alongside substantial harm and total loss.

Under HE6(4), where a proposal would harm the significance of a designated heritage asset, the effect on the asset and its significance is weighed against the public benefits of the proposal. Under HE6(5), the stricter test applies where the effect reaches substantial harm or total loss.

So “less than substantial harm” may still appear in older appeal decisions, local policy documents, heritage reports and current government guidance that has not yet been rewritten to match the August 2026 NPPF. It remains useful when reading historical decisions, but it is not the wording of the current national policy test. For a new application or appeal, the current HE policies should be used.

 

What counts as heritage harm?

 

Harm occurs where a proposal reduces or damages the significance of a heritage asset. That can happen through direct work to the asset or through development within its setting.

Examples might include removing historic fabric that contributes to a listed building’s special interest, disrupting a designed relationship between buildings and landscape, introducing development which competes with an important historic landmark, eroding the character or appearance of a conservation area, or obscuring archaeological evidence.

But change is not the same thing as harm. A proposal can alter an asset or its surroundings while leaving significance unharmed, and well-designed development can have a positive effect by restoring fabric, removing intrusive features, better revealing significance or securing a sustainable use.

This is why the phrase “it is in the setting of a listed building” is not enough to establish harm. The assessment has to explain how the setting contributes to significance and how the proposal changes that contribution.

 

What is substantial harm?

 

HE5 now gives a concise policy description: substantial harm occurs where development would seriously affect a key element of the heritage asset’s significance.

That is a high threshold, but it is not confined to total demolition. The question is qualitative. What element of significance is being affected, how important is it to the asset as a whole, and how serious would the effect be?

HE6 then makes the consequences clear. Development causing substantial harm or total loss to a designated heritage asset should be refused unless either:

• the harm is necessary to achieve substantial public benefits which outweigh that harm or loss
• all of the specific alternative tests in HE6(5) are satisfied, dealing with reasonable use, marketing, grant or not-for-profit/public ownership and the benefit of bringing the asset back into use

There is an additional policy warning about importance. Substantial harm or total loss of a Grade II listed building or Grade II registered park or garden should be exceptional. For assets of the highest significance, including scheduled monuments, protected wreck sites, registered battlefields, Grade I and Grade II* listed buildings, Grade I and Grade II* registered parks and gardens and World Heritage Sites, it should be wholly exceptional.

 

Any harm to a designated heritage asset carries serious weight

 

Do not read the substantial-harm threshold backwards. A conclusion that harm is not substantial does not make it trivial.

HE6(1) says substantial weight should be given to the conservation of a designated heritage asset, with greater weight for more important assets. HE6(3) then says that any harm to a designated heritage asset is a matter of considerable importance and weight.

That wording reflects the statutory approach explained by the Court of Appeal in Barnwell Manor Wind Energy Ltd v East Northamptonshire District Council & Others [2014] EWCA Civ 137. The case concerned permission for four wind turbines affecting the settings of several listed buildings, including the Grade I Lyveden New Bield. The Court held that section 66(1) requires the desirability of preserving a listed building’s setting to be given considerable importance and weight in the balancing exercise. The Inspector had identified harm but had not accorded the statutory objective the weight Parliament required, and the permission was quashed.

The same point was applied shortly afterwards in R (The Forge Field Society & Others) v Sevenoaks District Council [2014] EWHC 1895 (Admin). The proposed affordable housing would cause limited harm to the setting of a listed building and to the Penshurst Conservation Area. The council had balanced that harm against the benefits, but had not demonstrably applied the strong statutory presumption in favour of preservation. The planning permission was quashed.

The practical lesson is simple: limited harm is still heritage harm. It must be identified accurately and then given the weight required by statute and current policy before public benefits are placed on the other side of the balance.

 

How heritage harm is weighed against public benefits

 

For designated heritage assets, HE6(4) says that where a proposal would harm significance, the effect on the asset and its significance should be weighed against the public benefits of the proposal.

The word public matters. A private financial advantage to the applicant is not automatically a public benefit. Relevant benefits depend on the proposal and could include new homes, affordable housing, regeneration, community facilities, environmental improvements, bringing a vacant building back into long-term use, or improving energy efficiency where those benefits genuinely serve a wider planning purpose.

The 2026 NPPF itself gives two heritage-specific examples of important public benefits: securing the long-term reuse of a vacant or underused listed building and enabling energy-efficiency or low-carbon heating measures.

This is a weighted balance, not a mathematical subtraction. The decision-maker needs to understand the degree and nature of harm, the significance and importance of the asset, the statutory duty where one applies, and the nature, scale and certainty of the public benefits.

For substantial harm or total loss, HE6(5) raises the bar: the public benefits must themselves be substantial and must outweigh the harm or loss, unless the separate four-part alternative test is satisfied.

 

Designated and non-designated heritage assets are treated differently

 

A designated heritage asset includes listed buildings, scheduled monuments, conservation areas, registered parks and gardens, registered battlefields, protected wreck sites and World Heritage Sites. These are subject to HE6 and, where applicable, statutory duties.

Non-designated heritage assets, including many locally listed buildings, are dealt with under HE7. The policy still requires their significance and the harm to it to be understood, but it does not import the same HE6 statutory-weighting framework.

Where a proposal harms a non-designated heritage asset, HE7 requires a balanced judgment having regard to the scale of harm or loss and the significance of the asset. Where the effect would amount to substantial harm or total loss, the proposal should only be supported where the benefits outweigh that harm or loss, again having regard to the scale of the effect and the asset’s significance.

There is an important archaeological exception. A non-designated heritage asset of archaeological interest which the decision-maker considers to be of equivalent significance to a scheduled monument is treated under the policies for designated heritage assets.

 

The setting of a heritage asset can be part of its significance

 

The NPPF defines setting as the surroundings in which a heritage asset is experienced. Its extent is not fixed and can change as the asset and its surroundings evolve. Elements of setting can make a positive, negative or neutral contribution to significance.

Setting is therefore not a protective circle drawn at a standard distance around a listed building. It is also not the same thing as a building’s legal curtilage.

Views can be important, but setting is not purely visual. Historic relationships, movement, sound, landscape, spatial enclosure and the way places are experienced can all be relevant. Nor does a contribution to setting depend upon the public being able to enter the land.

Barnwell Manor is a useful illustration. The Court criticised the Inspector for not properly grappling with the contribution made by the undeveloped rural setting to the significance of Lyveden New Bield. The fact that public appreciation was one aspect of setting did not make it the only aspect.

For more detail, see our guide to the setting of a heritage asset, including distance, views, historic relationships, curtilage and the principles from Catesby Estates.

 

What should a heritage statement actually contain?

 

A heritage statement should be proportionate. HE5 does not require a dissertation for every minor proposal, but it does require enough information to understand significance and the effect of the development.

A useful statement normally does five things:

• identifies every heritage asset whose significance could realistically be affected, including relevant non-designated assets
• explains the significance of each asset and the contribution made by any relevant setting
• identifies which elements of significance the proposal would affect and how
• classifies the effect using the current HE5 language: positive effect, no effect, harm, substantial harm or total loss
• where harm remains, explains mitigation, alternatives and the public benefits relied upon in the relevant HE6 or HE7 balance

For archaeological interest, HE5 can also require a proportionate desk-based assessment and, where necessary, field evaluation.

The relevant Historic Environment Record should be consulted, and appropriate expertise used where necessary. Historic England’s guidance on statements of heritage significance remains useful for the methodology, although older guidance and PPG references must now be read alongside the changed August 2026 NPPF terminology.

Heritage information may sometimes sit within a design and access statement, but do not assume that a design narrative automatically answers the heritage-policy questions. Check the council’s validation requirements and, more importantly, make sure the information is sufficient to allow the decision-maker to apply HE5 and HE6 or HE7.

 

Can securing a viable use justify heritage harm?

 

Sometimes. Keeping a heritage asset in a viable use can be central to its long-term conservation, and the NPPF recognises the public benefit of securing the long-term reuse of a vacant or underused listed building.

That does not mean the most profitable use automatically wins. The proposal still needs to minimise harm and the heritage balance still has to be undertaken. Where substantial harm or total loss is proposed on the basis that no suitable use exists, HE6(5) specifically requires evidence addressing reasonable uses, marketing and whether conservation through grant funding or not-for-profit, charitable or public ownership is possible.

For an empty listed building, the commercial evidence and heritage evidence therefore need to speak to each other. A viability argument which ignores significance is incomplete, while a conservation solution which has no realistic prospect of being implemented may not secure the asset’s future.

 

Deliberate neglect or damage does not help the case

 

HE4 is explicit. Where there is evidence of deliberate neglect of, or damage to, a heritage asset, the deteriorated state of the asset should not be taken into account in a decision relating to it.

In other words, allowing a building to deteriorate is not a route to creating a stronger planning case for demolition or harmful redevelopment.

If a listed building is genuinely deteriorating, councils also have separate powers. See our page on listed buildings at risk, urgent works and repairs notices. Unauthorised works to a listed building raise a different and potentially criminal issue, covered in our guide to listed building enforcement.

 

A practical heritage significance and harm checklist

 

• Identify the asset correctly: listed building, conservation area, scheduled monument, registered asset, World Heritage Site or non-designated heritage asset
• Check the statutory duty: section 16, 66 or 72 may apply as well as the development plan and NPPF
• Define significance before discussing impact: say what matters and why
• Assess setting where relevant: explain its contribution rather than relying only on distance or visibility
• Use the current HE5 categories: positive effect, no effect, harm, substantial harm or total loss
• Do not equate small works with small harm: assess the effect on significance
• Minimise harm first: consider design changes, retention, repair, relocation within the site and realistic alternatives
• Identify genuine public benefits: state what they are, who benefits and how certain they are
• Apply the correct balance: HE6 for designated assets, HE7 for non-designated assets
• Give any heritage harm its proper weight: for designated assets, harm is not an ordinary material consideration to be casually outweighed

 

Relevant heritage legislation, policy and case law

 

• Planning (Listed Buildings and Conservation Areas) Act 1990, section 16, the listed building consent duty
• Planning (Listed Buildings and Conservation Areas) Act 1990, section 66, planning permission affecting listed buildings and their settings
• Planning (Listed Buildings and Conservation Areas) Act 1990, section 72, conservation-area duty
• Planning and Compulsory Purchase Act 2004, section 38, including the development-plan duty in section 38(6)
• National Planning Policy Framework, August 2026, especially HE4 to HE10 and the glossary
• Planning Practice Guidance: Historic environment, useful supporting guidance but with some heritage-harm terminology and NPPF paragraph references still reflecting the earlier Framework at the date this page was written
• Historic England GPA2: Managing Significance in Decision-Taking in the Historic Environment, noting Historic England is reviewing the document following NPPF changes
• Historic England Advice Note 12: Statements of Heritage Significance
• Barnwell Manor Wind Energy Ltd v East Northamptonshire District Council & Others [2014] EWCA Civ 137, approved Court of Appeal transcript hosted in Ashford Borough Council’s East Stour Solar Farm inquiry library
• R (The Forge Field Society & Others) v Sevenoaks District Council [2014] EWHC 1895 (Admin), on applying the statutory preservation duty in the planning balance
• South Lakeland District Council v Secretary of State for the Environment [1992] 2 AC 141, on preservation meaning the avoidance of harm
• Jones v Mordue [2015] EWCA Civ 1243, on section 66 compliance and the interpretation of decision reasons
• Palmer v Herefordshire Council [2016] EWCA Civ 1061, including non-visual effects on listed-building setting
• City & Country Bramshill Ltd v Secretary of State for Housing, Communities and Local Government [2021] EWCA Civ 320, on heritage harm, public benefits and the absence of any mandatory separate “internal heritage balance”

Conservation, Heritage & Protected Sites

 

Heritage Significance and Harm Page Updated: 21st August 2026