It has been long established in caselaw that harm to a designated heritage asset protected by the Planning (Listed Buildings and Conservation Areas) Act 1990 needs to be given considerable importance and weight in the planning balance, but the method of going about weighing harm against benefit has been less clear. The Palmer judgment suggested that an ‘internal heritage balance’ could be undertaken whereby the adverse and beneficial heritage impacts could be aggregated to legitimately give rise to a finding of no overall adverse effect. In this scenario, paragraph 196 of the NPPF would not be engaged. A recent Court of Appeal judgement ‘Bramhill’ has rejected the claim that the Palmer principle is the correct and only approach to the planning balance, ruling that there is no clear statutory requirement or reading of the NPPF that requires a ‘net’ balancing of heritage benefits and harm. It found that in this instance, the inspector’s approach of weighing the harm to heritage assets against the public benefits of the development, including the heritage-related public benefits, was lawful and methodically sound.
What remains clear is the great weight to be given to the asset’s conservation. This sounds a cautionary note when undertaken the planning balance for EIA development which requires an aggregation of the heritage impacts to give an overall significance of effect. It will be important that any harms to listed buildings and conservation areas even in the finding of a net benefit are demonstrably given great weight in the planning balance and justified accordingly.