19 Apr Surveying & Recording
According to the European Confederation of Conservator-Restorers’ Organisation’s (E.C.C.O.) professional guidelines, the role of the conservator-restorer is in the ‘preservation of cultural property for the benefit of present and future generations’. To complete this with confidence, it is often necessary to undertake a significant amount of research for most, if not all, of the projects we are involved with. This can be in the form of simply contextualising works for a small repair, but can often require the production of both survey documents and fully conclusive reports.
Guidelines such as Historic England’s ‘Understanding Historic Buildings: A Guide to Good Recording Practice’ (formally ‘RCHME guidelines – Recording Historic Buildings: A Descriptive Specification’) and the technical material they also publish are a useful set of parameters to try to work within and we aim to produce documentation in line with this and to a similar level and quality, that can, if called upon be utilised by different bodies.
Surveying and recording plays an important role in the long term strategising of conservation. Detailed surveys allow for a line to be drawn in the sand and a permanent record taken at that specific moment in time to be held on record and referred to. This then in turn, can help inform cyclical maintenance to aid preventative conservation and allow for the longer term planning of budget allocation for when interventional conservation is absolutely critical. The principles of building conservation philosophy should always be considered prior to making decisions relating to any intervention. The majority of these principles were established over 100 years ago by William Morris and associates within their manifesto in 1877 published for The Society of the Protection of Ancient Buildings (SPAB) and are still considered by many to be relevant today.
All works are normally recorded in a number of ways, these being in written form, through annotated drawings and from a good photographic archive.
Where materials are extremely vulnerable and at the point of major loss, we will often use a combination of methods to record them. This often starts with a close quarter visual survey to review and document existing condition. If intervention is proposed, then perhaps some localised trials are competed to gain more information on how best to conserve and restore them. On occasion, before any direct intervention is sanctioned, a 3D laser scan can also sometimes be employed to map all of the existing surfaces. The benefit of this, is that if any loss does occurr as a result of any delicate and considered cleaning regime implemented, a full record of the existing has already been undertaken and can form part of an historic archive.
Once recorded in full, conservation works can then be undertaken – safe in the knowledge that any inadvertent loss, has already been fully documented. On completion of any intervention, a secondary 3D laser scan can then also be completed. This will allow the original to be cross referenced and compared and can help calculate if any loss or micro abrasion has occurred.
As part of this wider recording process, analysis of historic material is an incredibly useful tool in helping us undertake sympathetic and more importantly, appropriate, repairs. It is often also useful to understand the differences between both original and later materials in terms of strength and permeability and to understand whether any changes have occurred as a direct result. The interpretation of analysis is perhaps even more important, as it also allows the identification of appropriate components to be used which will help match the original materials in composition, strength, colour and porosity.
This generally occurs in two forms within our works, further to mortar analysis, we also regularly undertake paint research. Its purpose is not just to understand the materials currently applied over a variety of differing substrates, but also often helps us map all chronological changes with a mind to identifying earlier schemes. All areas of intervention are of course recorded in both photographic and written forms with annotations often made onto drawings, which on completion, allow for us to interpret the results and then decide on the most appropriate combination of materials and colours for reinstatement.
BIM or building a ‘Building Information Model’ is a rather new and exciting development in the heritage sector. It is a fast-developing field in terms of research and now forms one of the most recent publications from Historic England (July 2017). BIM for Heritage is, by definition, a multi-disciplinary process that requires the input and collaboration of a range of professionals with very different skillsets.
BIM is being implemented to try and collate and present all relevant information in a single, accessible document. In the past, information relating to historic buildings and archaeological sites can often be found as a collection of individual documents, reports, drawings, computer files and datasets each provided by different professionals, working to their own standards with differing tools. BIM will allow all of this information to be accessible in a single multi-platform model that will require coordination between architects, engineers, M&E (mechanical and electrical installation), contractors and other professionals. The finished construct will be a 3D rendered record of all building components and spaces in a virtual representation.
The huge benefit of BIM is that once constructed, it can be queried intelligently in an ongoing manner, being used for further investigation and research by proposing conservation and management strategies without the need for any further intervention. The potential within the heritage world would as a result seem to be obvious and potentially game changing.