Last edited 31 Aug 2021

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Institute of Historic Building Conservation Institute / association Website

Guidance on Alterations to Listed Buildings

Guidance on Alterations to Listed Buildings.jpg
Guidance on Alterations to Listed Buildings was published by the IHBC in January 2021 as a digital document in the Toolbox on the IHBC website

The need for guidance relating to alterations to listed buildings became apparent when concerns surfaced a few years ago regarding a lack of consistency across the country on how different conservation advisors responded to a wide variety of proposed alterations to listed buildings.

The pioneering work of the IHBC south west branch, which included regional seminars on consistency, highlighted the need. There was a feeling that such inconsistency was in part due to a lack of detailed authoritative advice following the withdrawal, over 10 years ago, of guidance such as Annex C of the government’s PPG15 and Appendix 1 of Historic Scotland’s Memorandum of Guidance.

A considerable amount of guidance on built heritage conservation has been issued in the intervening years, but much of the content is relatively high-level advice. In relation to alterations, it does not drill down to many of the detailed issues faced day to day by professional heritage advisors. For example, published guidance invariably stresses the essential need to understand the heritage significance of a building before contemplating alterations, but none provides fine-grained good practice advice on such detailed matters as, for example, how to arrange pipework under a suspended timber floor when considering installation of service routes from, say, a new bathroom.

The document is not a rigid set of rules. It is intended as good practice guidelines, at a level of detail that is not currently available elsewhere. It starts by setting out general principles, and further general principles are put forward with regard to specific types of alteration. The alterations covered relate to walls, openings, roofs, other external factors, interiors, shops and commercial buildings, and modern fixtures, fittings and services.

As the IHBC is a UK-wide body, the guidance aims to provide advice that is common to all across the home nations. Key heritage organisations across the UK have been consulted. The initial draft, prepared by Bob Kindred, was developed by James Caird, Fiona Newton and her colleagues in the national office in the light of responses from consultees. The IHBC policy committee has kept a close eye on what has been a long process.

Given the breadth of the subject matter, it is not surprising that there has been some disagreement along the way and compromises have had to be made. However, I think the advice in the finalised document will be supported by most people whose aim is to ensure that alterations to listed buildings are carried out with sensitivity and in an informed manner. Not everyone may agree with every piece of advice, and some may feel that certain issues are not adequately covered. It is intended that the guidance should be a living document under continuous review, and that it will be amended periodically. Substantive advice on extensions to listed buildings is not included, as that is a subject in its own right that would have greatly expanded a document that already runs to 33 pages. Some comments have been received already, pointing out omissions. We would welcome further feedback to

This document alone is unlikely to overcome the concerns about inconsistency. It is hoped that once the pandemic is over, the consistency seminars pioneered by the south-west branch can be rolled out across the country through the IHBC branches, promoting a unified approach to historic building conservation.

This article originally appeared in Context 168, published by the Institute of Historic Building Conservation (IHBC) in June 2021. It was written by Roy Lewis, IHBC policy secretary.

--Institute of Historic Building Conservation

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