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The Role of Heritage Science in Conservation Philosophy and Practice
Craig J. Kennedy
School of Energy, Geoscience, Infrastructure and Society,
Heriot Watt University,
Edinburgh,
UK,
EH14 4AS
Email: [email protected]
Phone: +44 131 451 4629
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Abstract
For many years the relationship between science and conservation has been
growing. Scientific research to understand historic materials and inform evidence-led
conservation practices is increasingly seen as an important step towards ensuring
positive long-term outcomes for cultural property. ‘Heritage Science’ is emerging as
a discipline within its own right. The development of heritage science with specific
reference to its application to building conservation is considered. The role of
science within building conservation philosophy and practice is discussed, and
barriers to effective evidence-led conservation identified. A set of seven
recommendations for heritage science applied to building conservation are
proposed. It is expected that these recommendations, if implemented, will help to
balance the needs of heritage practitioners whose work aligns with conservation
philosophy, and scientists who require the ability to gather meaningful data from
historic buildings and sites. This is intended to encourage and enhance collaboration
between scientists and practitioners.
Keywords
Conservation, Heritage, Philosophy, Practice, Principles, Research, Science
Biography
Craig Kennedy is an Associate Professor at Heriot Watt University. Prior to this he
was Head of Science at Historic Scotland. His key research interest is historic
building materials decay and conservation.
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Introduction
Conservation, restoration and preservation of buildings and other historical artefacts
has gone on for centuries. In the 20th century, scientists took an increasing interest in
analysing materials of historic value, leading to discrete scientific disciplines such as
archaeometry, conservation science and artefact studies.
In recent years a new discipline has emerged which aims to encompass all of these
domains and bring them together to aid in conservation practice: heritage science.
The phrase ‘heritage science’ was coined in the UK in 2006 by the House of Lords
Science and Technology sub-committee report in to Science and Heritage1 as a
replacement for a collection of other terms such as ‘conservation science’ and
‘archaeological science’, though the previous terms still live on.
Following the House of Lords Report, a UK national heritage science steering
committee was formed, composed of members representing heritage agencies,
institutions and academia. This committee produced a number of publications: three
2,3,4 (outlining the role of science in the management of heritage assets; the use of
science to understand the past; and the capacity in the heritage sector at that time.
The committee’s final publication was the UK national heritage science strategy5
which set out aims and objectives for the heritage science sector, and recommended
the formation of a National Heritage Science Forum, which now exists.
This paper considers the practical application of heritage science to the building
conservation sector, and how best to marry conservation philosophy with scientific
investigations.
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Heritage Science as a Discipline
Many cultural institutions have a scientific research department which undertakes
research for the benefit of conservation. Over the last century many institutions have
incorporated a laboratory as part of the curatorial process when dealing with, for
example, museum collections. Early examples of laboratory installations include The
Staatliche Museum of Berlin, which opened a laboratory in 1888 and the British
Museum in London in 1919. Laboratories within museums increased in number after
World War I and again after World War II6. Built heritage organisations such as
Historic Scotland and English Heritage have employed scientific staff and equipped
laboratories in recent years with the aim of understanding the decay of building
materials, testing new conservation materials and providing evidence to aid in the
decision making process during conservation works. As well as undertaking direct
scientific work, these organisations work with a vibrant, international academic
community which retains a strong interest in understanding historic materials, their
decay and conservation in order to increase understanding of material properties at
a fundamental level7,8.
‘Conservation science’ existed for decades in this form before the emergence of the
term ‘heritage science’. Giovanni Urbani9 considered that conservation research
should evolve in to an independent scientific discipline, as scientists who were
primarily focused in non-heritage areas such as physics or chemistry would consider
only the constituent parts of a piece of cultural property, and not other aspects such
as aesthetic appreciation or heritage value. Considerable advancement has taken
place in the three decades since Urbani’s argument; Matija Strlic10 has set out a
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theoretical basis for heritage science based on a series of ten premises which
strongly consider the nature of the relationship between research and heritage value.
In the UK, matters coalesced in the mid-2000s with the House of Lords Science and
Technology sub-committee report into Science and Heritage1. This process involved
the gathering of evidence from across the scientific community working on the four
main areas of heritage: built heritage; collections; libraries and archives; and
archaeology. One outcome of this report was the formation of the UK national
heritage science strategy5 which sought to bring together a fragmented community
and encourage collaboration between scientists, conservation professionals,
heritage managers and stakeholders.
The national heritage science strategy gives two strategic aims:
‘1. Demonstrate the public benefit of heritage science and increase public
engagement and support for it.
2. Improve partnership within the sector and with others by increasing collaboration
to help practice make better use of research, knowledge and innovation and to
enhance resources, funding and skills.’
Each aim is underpinned by a number of objectives that will, if fully carried out,
improve the standing of heritage science. In terms of considering the application of
heritage science to building conservation philosophy and practice, the objective of
most relevance is:
‘Improving preservation.
The sector has made great strides in understanding materials and the mechanisms
of decay as well as developing ways to assess, monitor and record condition.
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Through the application of heritage science we will continue to improve conservation
practice ... ’5
This objective links heritage science to conservation practice, but as yet the linkage
between the two is informal and the practical application of heritage science to
building conservation has not fully been considered.
Building Conservation Philosophy and Practice
Historic building conservation, replication or restoration has existed in various forms
for centuries. Jukka Jokilehto11 details the development of international building
conservation philosophies from the Italian Renaissance through to the 20 th century.
Today, repairs to historic buildings and monuments should be carried out with an
understanding and basis within building conservation philosophy. International
charters by the International Council on Monuments and Sites (ICOMOS), the
manifesto of Society for the Protection of Ancient Buildings (SPAB) and other
publications have evolved and been updated over time to meet the developing ideas
behind sensitive conservation. Forster12,13 discusses the ethics and principles behind
building conservation philosophy for masonry repair. Briefly, these are listed as:
Ethics: authenticity; integrity; avoidance of conjecture; respect for age and historic
patina; respect for the contribution of all periods; inseparable bond with setting; rights
of the indigenous community.
Principles: minimal intervention; legibility (honesty and distinguishability); materials
and techniques (use of ‘like for like’ materials); reversibility; documentation;
sustainability.
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The British Standard which relates to conservation of historic buildings – BS 7913 –
was updated in 201314. This document brings the fundamentals of conservation
philosophy into practice, with a strong emphasis on heritage management,
conservation plans, values, significance, and how these relate to the flow of work
during conservation projects.
Further translating conservation philosophy to practice is the accreditation process
for professionals. Accredited conservators undergo rigorous evaluation to ensure
that their work portfolio is aligned with these philosophical points. The Institute for
Conservation (ICON) manages the professional accreditation for conservator-
restorers (PACR) process in the UK. This process encompasses conservators
working in all areas of heritage, and as such their guidance is not built heritage-
specific. The PACR guidance15 lists five key standards for members undergoing the
accreditation process: assessment of cultural heritage; conservation options and
strategies; conservation measures; organisation and management; and professional
development. Alongside these five standards are thirteen professional judgement
and ethics (J&E) principles, including ‘understanding principles and practice’ and
‘conversance with guidelines’.
The Institute for Historic Building Conservation (IHBC) has an accreditation process
for practitioners working specifically in the historic buildings sector. The IHBC
structures its accreditation process around the main elements of the ‘areas of
competence’. These areas of competence are divided into two sections: professional
and practical. Within the ‘professional’ competence, the membership standards,
criteria and guidelines16 states that professionals working in conservation require an
understanding of conservation philosophy and its application to practice.
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Heritage Science as a part of Conservation Philosophy
Ethical considerations of conservation philosophy do not occur in isolation. Scientific
research may have a part to play in ensuring the effective application of ethical
values to conservation.
When considering authenticity, the ability to distinguish between original material and
later repairs is important. In many cases scientific equipment may not be needed –
for example, plastic repairs from the latter half of the 20th century on a building that is
centuries old will be distinguishable to a competent practitioner. However, for other
forms where effort has been made to ensure that the repair is indistinguishable from
the original material, scientific methods may be needed to provide an additional
dimension to the available information. An example of the use of science to establish
authenticity is the identification of original window glass in historic buildings using
portable X-ray fluorescence17.
Integrity of a structure is discussed by Forster, who makes the distinction between
‘living’ and ‘dead’ buildings and how integrity may conflict with authenticity in these
cases. For a ‘living’ building which is still in use and functioning (as opposed to, say,
a ruin), the replacement of a failed section would require some scientific intervention
to ensure that the appropriate material is selected18.
The avoidance of conjecture (the need for incontestable evidence) and restoration
are wholly reliant on having as complete an evidence base as possible. Restoration
is taking a building back to a specific point in time and to do so effectively requires
interpretation of all the available evidence from that time. Forster notes that evidence
of this nature is rarely available without good historical documentation. Taking a
recent example, the restoration of the palace at Stirling Castle which was completed
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in 2011 relied on an extensive research programme analysing historic plans,
furnishings and excavation reports19. Scientific information has the potential to
complement such historical research, through the analysis of the building fabric to
determine origin, provenance or conservation history.
Respect for age and patina are considerations for conservation, as patina is
regarded as having aesthetic and historic qualities20 . Research has a role in this
regard, by ensuring that cleaning techniques are not overly aggressive. Disruptive
techniques have the potential to destroy the patina in order to make a material look
like new. Stone cleaning carried out using inappropriate methods in the 20 th century
has allowed buildings to lose their historic patina and, in some cases, discolour the
stone21. This realisation led to research into different methods that has allowed for
gentler methods of stone cleaning which retain the historic patina to be highlighted.
Similarly, research carried out on historic wrought iron has sought to develop a
cleaning method that will not disrupt the oxide layer that forms on the iron surface
over time, demonstrating that scientific testing can lead to positive outcomes from
cleaning that will not significantly harm the heritage value of an object or building22.
As well as ethical considerations, the principles of building conservation philosophy
can be enhanced through scientific input.
Perhaps the most obvious example is use of ‘like for like’ materials for repair, as it
may be necessary to scientifically determine which replacement material bears the
closest resemblance in terms of material properties to the original. A clear illustration
of this is petrographic analysis of building stones, a technique that considers which
stones available from currently operating quarries most closely match historic stones
in terms of properties such as porosity and sorting23. Over time, this will ensure that
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the replacement stone does not accelerate the decay of the historic stones
surrounding it, as can happen if a dense stone is placed in the midst of porous
stones, hastening the decline of the historic elements of the building fabric. Other
innovations in this field include the potential use of near-infrared spectroscopy (NIR)
and soil micromorphology to identify appropriate repair materials for earth
buildings24,25.
Scientific input has the potential to allow for a greater understanding of the condition
of existing historic sections of a building and may aid in keeping in place materials
that could otherwise be removed unnecessarily. This will aid in honouring the
principle of least or minimal intervention. Timber is a good example of this—timber
members within a building are visually assessed as part of a condition survey and a
decision is made to remove the member or keep it in place. The member may still be
load bearing but if the surface of the timber is eroded by, for example, rot or
woodworm the decision may be taken to remove it. Recent experiments have taken
place to attempt to develop a non-destructive acoustic method of assessing timber
strength in situ. This type of testing has the potential to protect many timbers within
historic buildings from being removed and replaced26.
Reversibility of a conservation application is an important philosophical principle. Any
action taken to conserve an object or building should have the ability to be removed
should it prove harmful to the substrate. Included in this are short-term remedies,
such as the application of facing materials to structural paintings for transportation
and storage. Theur27 conducted a series of experiments to understand the effects of
commonly used facing materials on long-term storage of paintings and painted
ceilings, and their ability to be removed after prolonged periods.
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The ability of science to influence and improve conservation has long been
recognised, and as such is included in international charters and professional
guidance. Article 2 of the ICOMOS Venice charter28 states:
‘The conservation and restoration of monuments must have recourse to all the
sciences and techniques which can contribute to the study and safeguarding of the
architectural heritage’
The ICOMOS charter ‘Principles for the analysis, conservation and structural
restoration of architectural heritage29’ considers the role of research more fully, and
has a key guiding principle listed as ‘Research and diagnosis’. This principle relates
to the approach that should be taken when undertaking research into historic
buildings, including two which specifically relate to scientific analysis of a building
(2.3 and 2.5). These can be summarised as the requirement for a full understanding
of the structural and material characteristics required in conservation practice; and
the approaches that should be made when diagnosing defects. Specifically, in terms
of science:
‘the quantitative approach mainly [based] on material and structural tests, monitoring
and structural analysis.’
An example of using science to diagnose defects in historic buildings is the analysis
of hair used in lime plasters30 which found that repair materials that have been pre-
treated with bleach or acid will lose performance significantly, leading to failures.
British Standard BS 791314 makes several explicit references to research in support
of evidence-led conservation, including a statement that good conservation depends
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on ‘a sound research evidence base and the use of competent advisors and
contractors.’
Two statements in the Standard clearly define the role of science as an essential
part of conservation work:
‘Work proposals should be based on an appropriate level of research into the historic
building in order to understand its significance, structure, fabric, design, layout,
services and other parameters.’
And:
‘The correct choice of materials for conservation works is important for historic
buildings. Where possible, existing materials should be investigated and tested so
that good performance and aesthetic matches can be achieved.’
The role of science has also made its way in to the professional accreditation
process for heritage practitioners. Standard 3 of the ICON guidance15 – conservation
measures – makes several references to taking in to account current research as
part of the decision-making process when considering conservation measures and
techniques. In 2006/7 the Institute of Conservation Science (ICS) joined ICON to
become the ICON Science Group. This merger was designed to improve the scope
for closer interaction between conservation and science.
The Institute for Historic Building Conservation (IHBC) recognises the value of
incorporating research to conservation, and has produced guidance to work towards
evidence-based conservation standards31. This stems from a belief that ‘effective
conservation standards should be developed out of research-based evidence
supported by practice-based guidance’. This statement clearly places research in a
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key role in the conservation process. The IHBC lists ‘Research, Recording &
Analysis’ as an area of competence in their membership standards, criteria and
guidelines, further aligning research and practical conservation for professional
members.
From these examples, it may be considered that science not only has a role to play
in informing conservation practice, but that scientific research is essential in ensuring
that conservation carried out is evidence-based, increasing the likelihood of a
positive outcome. Scientific research has been a central theme of conservation
philosophy for over half a century, though its utilisation in practice has perhaps not
been fully realised.
Barriers to Effective Heritage Science
Whilst the role of heritage science in conservation philosophy is explicitly stated in
conservation charters, it is often not possible to utilise heritage science fully for the
purposes of conservation.
One key issue faced by heritage scientists is sampling. In order to fully understand a
material, it may be necessary to extract sections to be taken for laboratory
investigations. Heritage managers are often reluctant to allow sampling, and if
allowed it is often at a level inadequate for statistically significant findings to be
gleaned.
This is perhaps related to heritage managers considering loss of historic fabric for
testing as inadvisable, or inappropriate. Under the heading ‘Heritage Management
Principles’ in BS 791314 it is stated that the principle of minimal intervention is
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important; that is, as much fabric as possible should be retained when a repair or
other intervention is required.
This leaves the heritage manager with the task of balancing the need for sampling in
order to gain an understanding of the building materials with the pressure to allow as
little material to be taken from the site as possible. Torraca32 describes balancing
minimum intervention and the requirement for testing as a ‘tightrope’ in the context of
stone conservation, whereby as little of the ‘information’ stored in objects is disturbed
as possible, whilst ensuring that the object can be preserved for the present and
future.
In many cases the level of sampling allowed is in proportion to the status of the
building being examined; a traditional building with no statutory protection such as
listed status may be sampled extensively with the owner’s permission, but a building
of national importance such as a scheduled ancient monument is unlikely to be
sampled at all. Ironically, conservation is allowed on many high-status buildings but
the lack of scientific input, brought about by a desire to protect the building, may lead
to a less than ideal long-term outcome from the conservation works.
A second issue facing heritage scientists is a lack of knowledge of the provenance of
a sample. It may be the case that the building under study is centuries old and has
undergone a series of changes over time, such as extensions, renovations,
restorations and conservation works. It may not always be apparent if a sample is
original to the building, or as the result of a later intervention. As such, one emerging
branch of heritage science is that of understanding provenance, as observed in
recent papers by Dungworth33, Avino & Rosada34 and Ortega et al35.
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Linked to the issue of provenance is the history of a sample. If a sample is original it
may have undergone conservation works in the past, and this may not be known to
the scientist if appropriate recording has not been taken. Here, it is important that a
scientist working on a building has access to conservation records so that it may
inform the results and recommendations arising from scientific investigation.
Strlic10 notes an issue regarding scientific values with regards to heritage science: it
can be neither experimental nor fundamental. When analysing historic items,
experiments are not repeatable and so taking a typical scientific approach to an
experimental programme is not possible in these instances. Equally, the objective of
heritage science is always known, and so it cannot be considered fundamental
research.
Developing a Set of Recommendations for Practicing Heritage Science
It is clear from the conservation charters and the national heritage science strategy
that science has a central role to play in informing conservation practice. Here, a set
of recommendations are proposed which are designed to meet the requirements of
scientists, conservators and heritage managers which share the same vision of
favourable outcomes for historic buildings following conservation interventions.
1. A team-based approach to developing evidence-based conservation.
This is a reflection of principle 2.1 of the ICOMOS charter ‘Principles for the analysis,
conservation and structural restoration of architectural heritage’. When undertaking
building conservation, the scientist should be part of the multidisciplinary team with a
specific remit to investigate the building and help inform the physical conservation of
the building. Ideally as part of a planning process scientific investigations should take
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place ahead of the conservation work. This form of interaction will help to highlight
the positive role that a scientist can take in the conservation process, and also help
the scientist take direction and understand underlying issues facing the building.
2. Preference for non-destructive or micro-destructive testing.
A major barrier to effective scientific input is the constraints placed on scientists
regarding sampling. Here, two approaches are proposed which will allow heritage
managers to be satisfied that excessive sampling is not taking place and allow the
scientist to glean meaningful, statistically significant data.
The recent development of portable laboratory equipment with capabilities
analogous to larger laboratory-based systems has allowed for an effective revolution
in heritage science. Recent advances in portable technology have included Near-
Infrared spectroscopy (NIR), X-ray fluorescence (XRF), hyperspectral imaging,
thermal imaging, laser scanning, Raman spectroscopy and many others.17,24,36,37,38,39
Such systems have allowed scientists to take the laboratory to the site, gathering a
large quantity of highly relevant data without the need for physical sampling. Where
appropriate and possible, non-destructive testing should be the preferred method of
scientific investigation of historic buildings and sites.
The type of equipment used should be appropriate for the type of information being
sought, and often more than one technique will need to be employed at any one
time.
It may also be the case that sampling is required, should such portable devices
either be unavailable or not suited for the type of scientific investigation needed. X-
ray diffraction is an example of a technique that is highly useful for the analysis of
16
stone and mortar materials, but is not available as a portable instrument. Should
sampling be required, it is recommended that a high number of very small samples
from various places across the area of interest (i.e. façade) are taken. Such micro-
testing is already in place in other sectors of heritage, for example micro-drilling of
parchment for document conservation40.
3. Gathering Large Data Sets
The nature of historic monuments and sites means that they often consist of a
collection of various materials combined to form the whole. The building may also be
subject to microclimates and discrete variations in fabric that mean different sections
of the building becoming weathered at different rates. As such, data should be taken
from across the whole site where possible. This would allow for a more complete
understanding of the behaviour of the whole area of interest and reduce the chances
that a sample taken from an unusual area – for instance, an area subjected to a
microclimate different from the rest of the site – could skew results and produce less
than ideal scientific conclusions. It is not advisable to take only a few samples, or
sample from a limited area, so as to extrapolate information on the whole building
from such small data sets may not be beneficial to conservation works.
4. Use of modern analogue materials
For robust scientific investigations on how a material may respond to specific
circumstances, the development of modern equivalents that can be tested
extensively is encouraged, though with caution. For example, Historic Scotland
commissioned the construction of experimental earth walls in locations across
Scotland to determine their responses to climate41. The same organisation also
constructed a sandstone wall in order to examine the effects of extreme salt
17
damage, exposing the analogue to conditions that would not be allowable on a
heritage asset (figure 1).
Strlic10 considers the benefits of using ‘mock or surrogate objects for research’. As
stated previously, scientific investigations taking place on historic materials are not
repeatable, and as such heritage science cannot be considered experimental.
However, when using analogous materials experiments can be reproduced allowing
for typical scientific principles to remain intact.
Care must be taken when comparing modern analogues to historical materials.
Historic building elements may have been constructed in a subtly different manner
from the modern analogues and will have been subjected to weathering over a long
period of time. Additionally, historic materials may be naturally different from modern
equivalents – one example is timber, which historically was slow grown for a longer
period of time compared to modern timber which may be faster grow for a shorter
period of time. Altering the growth regime for timbers in such a way will significantly
alter the physical properties42.
As such, although useful information may be gained from modern analogues, it may
be the case that historic building materials behave in a different manner.
5. Stress Testing (Artificial or Accelerated Ageing)
Accelerated or artificial ageing is a concept used in heritage science since the
nineteen fifties43. Much of the research carried out on accelerated ageing relates to
shelf life of perishable materials, and in the heritage sector the key output has been
for studies on historic paper. This form of testing requires a material to be placed in
an environmental chamber and exposed to extreme conditions; in theory, such
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conditions speed up the natural ageing of the material (figure 2). Such tests are done
in order to determine the effects of a conservation treatment or to evaluate the future
condition of a historic material44,45,46.
The basis for this type of test is the Arrhenius equation (figure 3), a formula for the
temperature dependence of chemical reaction rates. A generalisation of this
equation is that for common chemical reactions at room temperature, the reaction
rate doubles for each 10 degrees Celsius rise in temperature47. Extrapolating the
Arrhenius equation to a log-plot of reaction rates (k) or degradation times (1/k)
versus inverse temperature (1/T) should result in a straight line, allowing
extrapolations to be made at lower temperatures. Hence, for data gathered on a
material at high temperature over a period of weeks, the rate of degradation can be
calculated at low temperature for a period of years.
However, there is some scepticism as to the validity of these ageing methods as a
means of predicting behaviour of historic materials43,48. One argument against
Arrhenius ageing is that the equation was designed to consider elementary chemical
reactions, whilst historic materials are complicated aggregates of differing systems.
Another is that Arrhenius behaviour does not match experimentally derived data49.
To improve accelerated ageing results, more complicated systems of ageing have
been proposed which include elevated temperature, controlled humidity, irradiation,
and the inclusion of pollutants47,50. However, no standard method of accelerated
ageing has yet been devised that can accurately predict the behaviour of a building
material after many years of natural ageing.
For the purposes of understanding reactions of historic building materials to
environmental conditions, it may be wise to stop references to ageing and instead
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replace these forms of experiments with a title such as ‘stress tests’. Such tests are
valuable in determining a material’s durability following conservation works.
Renaming these tests will remove the inference that the results of such experiments
are representative of the future condition of samples.
6. Openness of Access to Experimental Data
Recording and documentation is a principle of building conservation. This is
essential in tracking the changes undergone over the lifetime of a building. Regular
condition surveys chart the emergence of any potential problems that threaten the
building. More recently laser scanning has become an integrated part of the
condition survey36. When building conservation works are carried out extensive
reports are written, photographs taken and the final work is archived for future
conservators. Results of scientific investigations should be included as part of the
building conservation records with a similar view in mind: in future years, when
conservators and scientists revisit a site they should have access to as much
detailed information as possible about the building they are about to embark working
on.
As well as summary reports of scientific investigations, raw data should be included
where possible so that comparisons may be made in future which may highlight any
changes that have taken place to the material over time.
Additionally, publication of scientific material relating to conservation should be
encouraged. For evidence-led conservation to become the norm, the overall
knowledge base regarding traditional building materials must be increased. This
would allow scientists worldwide to have access to a wealth of data which may
inform their own conservation programmes.
20
7. Integrating heritage science as part of the overall heritage experience
Heritage science is an increasingly significant aspect of conservation work. Where
possible, the investigative aspects of conservation should also be highlighted. This
will boost both the profile of heritage science, and also enhance the public
understanding of how key decisions are reached with regards to conservation.
Heritage institution websites, magazines and technical publications often hold
articles on how an object or building was investigated and conserved51,52. This level
of openly available information has the potential to expand the visitor experience,
and consideration should be taken as to how this could be achieved.
This principle links directly to the strategic aim of the national heritage science
strategy to demonstrate the public benefit of, and increase support for, heritage
science.
Conclusion
Here, seven recommendations are suggested which relate to how heritage science
can be of practical help to building conservation works, enhancing the quality and
outcomes of conservation work. These principles align with the established
philosophical basis for conservation of buildings. On a practical level, these also aim
to balance the needs of the scientist with heritage management principles.
21
References
1 House of Lords Science and Technology Select Committee, 2006, Enquiry report on Science and Heritage. HL 256, London: The Stationery Office Limited.
2 Jim Williams, ‘The role of science in the management of the UK’s heritage’, National Heritage Science Strategy (London: English Heritage, 2009) [online] <http://www.heritagescienceforum.org.uk/test/images/dynamicImages/file/nhss_report_1_web.pdf> [accessed 6th
May 2015]
3 Jim Williams, ‘The use of science to enhance our understanding of the past’, National Heritage Science Strategy (London: English Heritage, 2009) [online] <http://www.heritagescienceforum.org.uk/test/images/dynamicImages/file/nhss_report_2_web.pdf> [accessed 6th
May 2015]
4 Jim Williams, ‘Understanding capacity in the heritage sector’, National Heritage Science Strategy (London: English Heritage, 2009) [online] <http://www.heritagescienceforum.org.uk/test/images/dynamicImages/file/nhss_report_3_web.pdf> [accessed 6th
May 2015]
5 Sarah Staniforth, Peter Brimblecombe, Craig Kennedy, Katy Lithgow, Nick Merriman, Sebastian Payne, Mark Pollard, Helen Shenton, Jim Tate, Heather Viles, David Watkinson, ‘Our vision and strategy for heritage science’ , National Heritage Science Strategy (London: English Heritage, 2009) [online] <http://www.heritagescienceforum.org.uk/test/images/dynamicImages/file/
nhss_vision_strategy_web.pdf> [accessed 6th May 2015]
6 Paul Coremans, ‘La recherché scientifique et la restauration des tableaux’ Bulletin de l’Institut Royal du Patrimoine Artistique 4 (1961) pp 109-15
7 Historic Scotland, ‘Technical Research Plan, 2014-15’ Historic Scotland Conservation Directorate (Edinburgh, Historic Scotland, 2014) [online] <http://www.historic-scotland.gov.uk/hscd_research_plan_2014-2015.pdf> [accessed 6th May 2015]
8 Jim Williams, Edmund Lee, Gill Campbell, EH Science Network, ‘English Heritage Science Strategy’ (London, English Heritage, 2013) [online] https://content.historicengland.org.uk/images-books/publications/ehss/EHSS.pdf/ [accessed 6th May 2015]
9 Giovanni Urbani, ‘La scienza e l’arte della conservazione dei beni culturali’ in La Scienza e l’arte della Conservazione: Storici dell’arte, Tecnici, Restauratori a Confronto sui Temi Ancora Irrisolti del Restauro. Ricerche di Storia dell’arte 16 (Rome, La Nuova Italia Scientifica, 1982) pp 7-10
10 Matija Strlic, ‘A brief theory of heritage science’ (London, National Heritage Science Forum, 2015) [online] <https://nationalheritagescienceforum.wordpress.com/2015/04/16/a-brief-theory-of-heritage-science-by-professor-matija-strlic-ucl-institute-for-sustainable-heritage/> [accessed 6th May 2015]
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1 Jukka Jokilehto, ‘A History of Architectural Conservation’, D.Phil Thesis, University of York, 1986
2 Alan M. Forster, ‘Building conservation philosophy for masonry repair: part 1 – “ethics”’, Structural Survey, 28 (2010) pp 91-107
3 Alan M. Forster, ‘Building conservation philosophy for masonry repair: part 2 – “principles”’, Structural Survey, 28 (2010) pp 165-88
4 Technical Committee B/560 Conservation of tangible cultural heritage, BS7913:2013 Guide to the Conservation of Historic Buildings (London: British Standards Institute, 2013)
5 Institute of Conservation, ‘PACR Professional Standards’ [online] <http://www.icon.org.uk/images/new_pacr_professional_standards_2.pdf> [accessed 6th May 2015]
6 Institute of Historic Building Conservation, ‘Membership Standards, Criteria and Guidelines’ [online] <http://ihbc.org.uk/resources/MembershipStandardsandGuidelines0308.pdf> [accessed 6th May 2015]
7 Craig J. Kennedy, K. Robin Murdoch, Alan M. Forster, ‘Assessment of the survival of historic window glass using X-ray fluorescence at Newhailes, Edinburgh’ Glass Technology: European Journal of Glass Science and Technology Part A 56:2 (2015) pp. 63-69
8 John J. Hughes, Jan Valek, ‘Mortars in historic buildings’ (Historic Scotland TCRE, Edinburgh, 2003)
9 Historic Scotland, ‘Stirling Castle Palace: Archaeological and Historical
Research’ [online] <http://sparc.scran.ac.uk/home/homePage.html> [accessed 6th May 2015]
20 D. Bell, Technical Advice Note 8: The Historic Scotland Guide to International Charters (Historic Scotland, Edinburgh, 1997)
21 C. Andrew, S. Baxter, J. MacDonald, M. Rocha, B. Thomson, K. Tonge, D. Urquhart, R. Webster, M.E. Young, ‘Stonecleaning in Scotland’ (Historic Scotland, Edinburgh, 1992)
22 Nicola Emmerson, David Watkinson, ‘Preparing historic wrought iron for protective coatings: quantitative assessment to produce evidence-based protocols’ in: Metal 2013, Edinburgh, Scotland. Interim meeting of the International Council of Museums Committee for Conservation Metal Working Group. Ed. by Ewan Hyslop, Vanesa Gonzalez, Lore Troalen, Lyn Wilson. (Edinburgh: Historic Scotland, 2014) pp. 119-27.
23 Ewan Hyslop ‘Sourcing and selection of stone for repairs’ in Stone Conservation: Principles and Practice ed. by Alison Henry (Shaftsbury: Donhead, 2006) pp 89-99
24 Simon J. Parkin, W. Paul Adderley, Maureen E. Young, Craig J. Kennedy, ‘Near infrared (NIR) spectroscopy: a potential new means of assessing multi-phase earth-built heritage’ Analytical Methods 5 (2013) pp. 4574-79
25 W. Paul Adderley, Simon J. Parkin, Dorothy A. McLaughlin, Craig J. Kennedy, ‘Novel micro-scale techniques to establish a life-cycle analysis of earth-built structures in Scotland’ Proceedings of the 11th International Conference on the Study
23
and Conservation of Earthen Heritage (Peru, ICOMOS, 2012)
26 D. Ridley-Ellis, C-M Popescu, ‘Acoustic Assessment of Timber from 16th Century Painted Timber Ceilings in Scotland’. Proceedings of the 4th European Symposium on Religious Art Restoration and Conservation (ESRARC) (Iasi, Romania, 2012)
27 Chantal-Helen Theur, ‘Scottish Renaissance Interiors: Facings and adhesives for size‐tempera painted wood’ Historic Scotland Technical Paper 11 (Historic Scotland, Edinburgh, 2011)
28 ICOMOS, ‘The Venice Charter, (Venice, Italy, 1964) [online] <www.icomos.org/charters/venice_e.pdf> [accessed 6th May 2015]
29 ICOMOS, ‘Principles for the analysis, conservation and structural restoration of architectural heritage’, (Victoria Falls, Zimbabwe, 2003) [online] <http://www.international.icomos.org/victoriafalls2003/struct1_eng.htm> [accessed 6th May 2015]
30 Craig J. Kennedy, William A. Revie, Matthew Wade, Tim J. Wess, ‘Studies of hair for use in lime plaster: implications for conservation and new work’, Polymer Degradation and Stability 98:4 (2013) pp.894-98
31 Institute of Historic Building Conservation, ‘Operational Principles for Integrating IHBC’s research, guidance and advocacy for the production of Standards; a Strategy for Evidence-based Conservation Standards in the IHBC’ [online] <http://ihbc.org.uk/resources/Operational-principles-for-integrating-IHBCs-research_guidance-and-advocacy-
October-2014.pdf > [accessed 6th May 2015]
32 Giorgio Torraca, ‘The scientist’s role in historic preservation with particular reference to stone conservation’ in Conservation of Historic Stone Buildings and Monuments; Report of the Committee on Conservation of Historic Stone Buildings and Monuments (Washington D.C., National Academy Press, 1982) pp 13-18
33 David Dungworth, ‘The value of historic window glass’ The Historic Environment, 2:1 (2011) pp. 21-48
34 Pasquale Avino, Alberto Rosada, ‘Mediterranean and Near East obsidian reference samples to establish artefacts provenance’, Heritage Science, 2:16 (2014) pp 1-11
35 L.A. Ortega, M.C. Zuluaga, A. Alonso-Olazabal, M. Insausti, A. Ibanez, ‘Geochemical Characterisation of Archaeological Lime Mortars: Provenance Inputs’, Archaeometry 50:3 (2008) pp 387-408
36 David Barber, Jon Mills, ‘3D laser scanning for heritage’ (English Heritage Publishing, London, 2011)
37 Christian Fischer, Ioanna Kakoulli, ‘Multispectral and hyperspectral imaging technologies in conservation: current research and potential applications’ Studies in Conservation, 51 (2006) pp 3-16
38 Samira Nikzad, Behrouz M. Kari, Farhang Tahmadebi, ‘The application of thermal imaging as a non-destructive test in historic buildings’ International Conference on Durability of Building Materials and Components (Porto, Portugal, 2011)
24
39 Concepcion Domingo, Monica Alvarez de Buergo, Santiago Sanchez-Cortes, Rafael Fort, Jose V. Garcia-Ramos, Miguel Gomez-Heras, ‘Possibilities of monitoring the polymerization of silicon-based water repellents and consolidants in stones through infrared and Raman spectroscopy’ Progress in Organic Coatings, 63 (2008) pp 5-12
40 Microanalysis of Parchment ed. by Rene Larsen (London, Archetype Publications, 2002)
41 Bruce Walker, Christopher McGregor, Technical Advice Note 6: Earth Structures and Construction in Scotland (Edinburgh: Historic Scotland, 1996) pp 105-06
42 T. Fish, R. Wilson, C. Edwards, C. Mills, A. Crone, A.J. Kirchefer, H.W. Linderholm, N.J. Loader, E. Woodley, ‘Exploring for senescence signals in native scots pine (Pinus sylvestris L.) in the Scottish Highlands’ Forest Ecology and Management, 260 (2010) pp. 321-30
43 Henk Porck, Rate of Paper Degradation: The Predictive Value of Artificial Aging Tests (Amsterdam: European Commission on Preservation and Access, 2000)
44 A.M. Seves, S. Sora, G. Scicolone, G. Testa, A.M. Bonfatti, E. Rossi, A. Seves, ‘Effect of thermal accelerated ageing on the properties of model canvas paintings’ Journal of Cultural Heritage 1:3 (2000) pp.315-22
45 H.C. Inigo, S. Vicente-Tavera, V. Rives, ‘MANOVA-biplot statistical analysis of the effect of artificial ageing (freezing/thawing) on the colour of treated granite stones’, Color Research & Application, 29:2 (2004) pp 115-20
46 J. Garcıa-Talegon, M.A. Vicente, S. Vicente-Tavera, E. Molina-Ballesteros, ‘Assessment of Chromatic Changes Due to Artificial Ageing and/or Conservation Treatments of Sandstones’, Color Research & Application, 23:1 (1998) pp 46-51
47 Catherine E. Housecroft, Edwin C. Constable, ‘Reaction kinetics’ Chemistry: An Integrated Approach (Harlow: Longman, 1997) pp. 459-503 (p.484)
48 Helmut Bansa, ‘Accelerated Aging in Conservation Research: Some Ideas for a Future Method’, Restaurator 13:3 (1992) pp 114-37
49 K.T. Gillen, M. Celina, R.L. Clough, J. Wise ‘Extrapolation of accelerated aging data – Arrhenius or erroneous?’ Trends in Polymer Science, 5 (1997) pp. 250-57
50 Naomi Luxford, David Thickett, ‘Designing accelerated ageing experiments to study silk deterioration in historic houses’ Journal of the Institute of Conservation 34:1 (2011) pp. 115-27
51 Quanyu Wang, Sascha Priewe, ‘Scientific analysis of a Buddha attributed to the Yongle period of the Ming dynasty’, The British Museum Technical Research Bulletin 7 (2013) pp 61-68
52 Historic Scotland, ‘Focus 2015’, Historic Scotland Conservation Directorate (Historic Scotland, Edinburgh, 2015) [online] <http://conservation.historic-scotland.gov.uk/focus-magazine-2015.pdf> [accessed 6th May 2015]
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