A recent judgment in the High Court has clarified that "negligible" effects are material, and while the level of harm may be minimal this still engages paragraph 196 of the National Planning Policy Framework (NPPF), which requires public benefits of the development proposals to be weighed against the harm.
R.(James Hall and Company Limited) v City of Bradford Metropolitan District Council and Co-Operative Group Limited  EWHC 2899 (Admin) relates to the demolition of a fire station in Haworth Conservation Area (CA). While the building is of no interest, the Planning Statement identified "negligible" effects on views of the grade II listed Bridgehouse Mills and the CA.
J. Belcher concluded that the negligible effects on these heritage assets was material, and while the degree of harm was minimal, this still engaged paragraph 196 of the NPPF. The Officer Report therefore took an unlawful approach when failing to consider these heritage effects.
In paragraph 34 J. Belcher states:
"In my judgment the three categories of harm recognised in the NPPF are clear. There is substantial harm, less than substantial harm and no harm. There are no other grades or categories of harm, and it is inevitable that each of the categories of substantial harm, and less than substantial harm will cover a broad range of harm. It will be a matter of planning judgment as to the point at which a particular degree of harm moves from substantial to less than substantial, but it is equally the case that there will be a number of types of harm that will fall into less than substantial, including harm which might otherwise be described as very much less than substantial. There is no intermediate bracket at the bottom end of the less than substantial category of harm for something which is limited, or even negligible, but nevertheless has a harmful impact. The fact that the harm may be limited or negligible will plainly go to the weight to be given to it as recognised in Paragraph 193 NPPF. However, in my judgment, minimal harm must fall to be considered within the category of less than substantial harm."
Sometimes "negligible" is used as a shorthand for an effect that does not matter either way. A sharper approach is now required which identifies clearly whether a proposal is harmful or not, rather than relying on this somewhat vague term. Outside an Environmental Impact Assessment, where "negligible" has a defined meaning, I have tended to avoid using the term for this reason.
This is the latest in a number of heritage judgments that have increasingly emphasised the importance of protecting our historic environment. This, of course, is no bad thing, although now even negligible effects to listed buildings and conservation areas will be of "great weight" in the planning balance. This is a further tightening of the screw in heritage protection.