The harm and public benefit balance in a Heritage Statement

The less than substantial harm public benefit balance is where most Heritage Statements are won or lost, and it is the section that most often reads as an afterthought. The exercise has a fixed shape. Identify the significance of the asset. Identify the harm the proposal causes to that significance, and grade it. Give that harm great weight. Identify the public benefits, evidence them, and weigh them against the harm as graded. Reach a conclusion that says which way the balance falls and why.

Skip a step and the section stops being a balance at all. A list of benefits with no articulated harm is not a balancing exercise, and an inspector will say so.

The statutory duties that sit underneath

Two duties in the Planning (Listed Buildings and Conservation Areas) Act 1990 come before any policy.

Section 66 requires the decision maker, in considering whether to grant permission for development which affects a listed building or its setting, to have special regard to the desirability of preserving the building, its setting and any features of special architectural or historic interest it possesses. Section 72 requires special attention to be paid to the desirability of preserving or enhancing the character or appearance of a conservation area. Section 16 imposes the equivalent duty on applications for listed building consent.

The Court of Appeal in Barnwell Manor made the consequence plain. These duties are not a neutral factor to be placed on the scales alongside others. Considerable importance and weight must be given to the desirability of preserving the asset, and there is a strong statutory presumption against granting permission where harm would be caused.

A Heritage Statement that discusses national policy without mentioning the statutory duties has missed the foundation of the exercise. Name the sections, state what they require and show that the balance has been conducted with that weighting applied.

Substantial harm against less than substantial harm

The Framework divides harm into two categories, and the consequence of the division is severe.

Substantial harm to a designated heritage asset should be exceptional, and wholly so for the highest grades. Where it arises, it should be refused unless it is necessary to achieve substantial public benefits that outweigh the harm, or a defined set of alternative circumstances applies. Less than substantial harm is weighed against the public benefits of the proposal, including securing the optimum viable use of the asset.

The threshold for substantial harm is high. It is generally understood as harm that would have a serious effect on the significance of the asset, draining away or vitiating a very important part of it. Demolition of a listed building is the clearest example. Loss of a substantial part of its historic fabric or of the setting that gives it meaning can also reach it.

Two errors recur in drafting. The first is grading harm as less than substantial without saying where within that range it falls, because less than substantial covers everything from barely perceptible to close to the threshold, and the weight given to it should differ accordingly. The second is arguing there is no harm at all when the honest answer is a low level of harm. Overclaiming on this point costs credibility for the rest of the Heritage Statement.

Where great weight attaches and what it means

Great weight is given to the conservation of designated heritage assets, and the more important the asset the greater that weight should be. It applies irrespective of whether the harm is substantial, less than substantial or amounts to total loss.

In practice that means the harm side of the balance starts heavier than its apparent scale suggests. A modest degree of harm to a Grade I listed building is not a modest consideration. A comparable degree of harm to an unlisted building in a conservation area, which is a non-designated asset unless the area itself is the asset in question, is weighed differently.

Say in the statement which category the asset falls into, its grade where designated, and what follows for the weight. Assessors read that paragraph to see whether the author understands the framework they are applying.

Identifying public benefits that count

A public benefit is a benefit to the public at large, of a nature or scale sufficient to weigh in the balance. It does not have to be public in the sense of being publicly accessible, and it need not be the sole purpose of the development. But it does have to be more than a private benefit to the applicant.

Benefits that commonly count:

• Securing the optimum viable use of an asset at risk, with evidence that the alternative is continued decay.
• Repair and restoration of historic fabric, specified and secured by condition or obligation.
• Delivery of housing, including affordable housing, where the local position gives it weight.
• Economic benefits, employment and the reuse of a vacant building in a town centre.
• Public access to an asset that has not been accessible, secured by agreement.
• Environmental improvements, including removal of unsympathetic later additions.

Benefits that generally do not: the applicant's profit, the avoidance of cost, the delivery of a scheme the applicant prefers, and improvements that would happen anyway.

Evidence each benefit. A housing benefit needs a figure and a policy context. A repair benefit needs a schedule of works. An employment benefit needs an estimate with a basis, which is where an Economic Impact Assessment does real work rather than decorative work.

Weighing benefits against the level of harm

The balance is not arithmetic and should not be presented as though it were. What it requires is a clear statement of what is being weighed against what.

A usable structure runs like this. Restate the harm and its grading in one sentence. Restate the weight the statute and policy require. List the benefits with the weight attributed to each and the evidence behind it. Then state the conclusion and the reason for it, addressing the strongest point against you rather than ignoring it.

Where the harm is at the lower end of less than substantial and the benefits include an evidenced optimum viable use, the balance usually falls in favour. Where the harm is towards the upper end and the benefits are generic, it usually does not. Saying so plainly, including where the answer is uncomfortable, produces a statement an officer can rely on.

Appeal decisions are useful for seeing how inspectors have approached similar facts, and they are indicative rather than binding. Read them for reasoning, not for outcomes.

Common drafting errors in the balance

Where setting is in issue, the assessment should follow a recognised staged approach to identifying the setting, understanding how it contributes to significance and assessing the effect of the proposal on it. Where townscape is the medium through which harm arises, a Townscape and Visual Impact Assessment provides the visual evidence the heritage argument rests on, and the two documents should agree with each other.

One honest observation. The hardest part of this section is not the law. It is persuading a client that admitting a low level of harm strengthens the case rather than weakening it. It almost always does.

This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it, and verify the current Framework edition and its historic environment policies at the time of writing.

PlanScope can draft the significance, harm and balance sections for a heritage specialist to review and complete. Browse the report types and start a draft. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.