Planning decisions are a matter of balance, weighing up the positive benefits of a proposal against any negative consequences – called “the planning balance”.
Until a couple of years ago, there was a tendency to give insufficient weight to heritage and conservation assets in judging this balance. This was despite the Planning (Listed Buildings and Conservation Areas) Act 1990. Section 66 of the Act[i] says:
In considering whether to grant planning permission for development which affects a listed building or its setting, the local planning authority or, as the case may be, the Secretary of State shall have special regard to the desirability of preserving the building or its setting or any features of special architectural or historic interest which it possesses.
The debate over heritage protection and planning came to a head in 2012 when a planning inspector approved four wind turbines overlooking the Grade I heritage assets at Lyveden New Bield in Northamptonshire.[ii] His decision was rejected by the high court in 2013 and then by the appeal court a year later, a decision known as the Barnwell Manor judgement.
Turley Associates gives a fair summary of the two judgements. The critical point is that decision-makers should give “considerable importance and weight” to the desirability of preserving the setting of listed buildings when making planning decisions. These judgements have since been cited on numerous occasions by planning inspectors and the secretary of state for communities when rejecting appeals for developments, citing less than substantial harm.
In his decision on Penshurst in Kent, Justice Lindblom also gave a succinct summary of the Barnwell judgement:
As the Court of Appeal has made absolutely clear in its recent decision in Barnwell, the duties in sections 66 and 72 of the Listed Buildings Act do not allow a local planning authority to treat the desirability of preserving the settings of listed buildings and the character and appearance of conservation areas as mere material considerations to which it can simply attach such weight as it sees fit. If there was any doubt about this before the decision in Barnwell it has now been firmly dispelled. When an authority finds that a proposed development would harm the setting of a listed building or the character or appearance of a conservation area, it must give that harm considerable importance and weight.
This does not mean that an authority’s assessment of likely harm to the setting of a listed building or to a conservation area is other than a matter for its own planning judgment. It does not mean that the weight the authority should give to harm which it considers would be limited or less than substantial must be the same as the weight it might give to harm which would be substantial. But it is to recognize, as the Court of Appeal emphasized in Barnwell, that a finding of harm to the setting of a listed building or to a conservation area gives rise to a strong presumption against planning permission being granted. The presumption is a statutory one. It is not irrebuttable. It can be outweighed by material considerations powerful enough to do so. But an authority can only properly strike the balance between harm to a heritage asset on the one hand and planning benefits on the other if it is conscious of the statutory presumption in favour of preservation and if it demonstrably applies that presumption to the proposal it is considering.
There remains a common confusion about “less than substantial harm.” Many people think this means “insignificant harm” in planning terms. It does not. As national planning practice guidance makes clear: “substantial harm is a high test, so it may not arise in many cases.” Less than substantial harm can sometimes have a significant impact on a heritage asset or conservation area. And that impact must be given considerable weight in planning decisions.
Historic England has published advice on assessing significance: Historic Environment Good Practice Advice in Planning Note 2.
[i]. Section 72 of the 1990 Act gives equivalent protection for conservation areas.
[ii]. I was somewhat apoplectic about this decision at the time: Is it time to abolish the Planning Inspectorate to stop further travesties like the Lyveden wind farm?