Page 7 - Historic Churches 2013

BCD Special Report on Historic Churches 20th annual edition 7 CATHEDRALC O M M U N I C A T I O N S
through the side panels resulting in twisting,
warping, loss of jointing material, loss of
chest lids and, in extreme cases, the collapse
of the whole monument into a void. The
latter can result in the discovery of human
remains which will require an archaeological
assessment and an urgent health and safety
review of public access to the churchyard.
The next key cause of surface and structural
decay is the presence of iron fixings which were
widely used as structural ties in churchyard
monuments. Over time the iron is exposed to
damp moving through the porous structure of
stone and mortar. Iron is subject to corrosion
in the presence of moisture and the volumetric
increase caused by the corrosion exerts pressure
on the surrounding stonework resulting in the
opening up of the joints and associated loss
of surface. As the iron becomes increasingly
exposed to the air, the decay mechanism
causing the volumetric increase of the iron
accelerates and the monument is subject to a
dramatic loss of surface and structural integrity
that will eventually cause it to collapse.
The decorated and inscribed stone surfaces
of churchyard monuments are also subject
to surface decay through weathering and the
presence of salt crystallisation in the porous
structure of the stonework. Salt deterioration
problems are complex and any attempt to
remedy them should begin by establishing
the nature of the salts present and how they
are delivered into the masonry. That said, it
is clear that repeated cycles of salts moving
in and out of solution impose considerable
stress on the pore structure resulting in
disaggregation and loss of surface detail.
Lamination of the surface is also associated
with salt movement in cases where a section
of a sedimentary stone has been inserted
into the monument out of its natural bed
(the plane in which the stone formed). Loads
should always be carried at right angles to
the bedding plane, but masons often found it
expedient to use slabs of sandstone or limestone
in the wrong plane. Moisture ingress and salt
distribution will exploit the inherent weakness
of a stone bed which is under pressure.
SURVEY AND REPAIR
The decay mechanisms described above have
an impact on both the monuments and on
safe access to the churchyard. Furthermore,
if a monument becomes so badly damaged
that it can no longer serve its purpose as a
dedication to and record of an individual within
a community, the character of the churchyard
is diminished. Maintaining the vegetation
around unstable and collapsed monuments is
also more difficult and the balance between
the monuments and their setting can be lost.
In most cases where there are concerns
over churchyard monuments and in particular
where there are several of them, the first
step is to request quotes for a condition and
recommendation report. The first hurdle for
the custodians of the monuments at risk is to
obtain funding for this report which then can
become an important tool in constructing a
forward-looking strategy for the monuments
and for making faculty applications. A detailed
condition and recommendation report will
provide important information on the current
condition of the monuments and, where
more than one is at risk, should list them in
order of priority for treatment. It can also
then provide a benchmark against which the
rates of decay can be measured. If it does not
already exist, a simple numbering system for
easy identification of the monuments should
be created. This will be an invaluable tool for
recording the location, design and condition
of each monument in the churchyard.
The report should also provide budget
sums for a best practice conservation
programme in order to enable the custodians
to begin to apply for grants both for individual
monuments and for more wide-ranging
programmes of work to groups of monuments
or to the landscape of the churchyard. Grants
for the conservation of churchyards are
now available through a number of heritage
agencies (see Further Information).
At this stage it can be beneficial to
consider how to involve the community and
local schools in the conservation project.
Churchyard monuments provide an excellent
opportunity to research the social history of
the community and the personalities behind
the monuments. For example, past projects
have involved local schoolchildren creating
time capsules to put inside monuments
which need to be rebuilt. Such projects
give the younger generation a greater
understanding of the church and churchyard
and can help to create a sense of shared
ownership and pride in the local heritage.
Once funding is in place it is important
to plan each step of the process and prepare
risk assessments and method statements for
each stage. Although it is important for the
West Littleton Churchyard, Wiltshire: an example of surface lamination across an inscription panel resulting in
extensive loss of the stone surface
Buckland Newton Churchyard, Dorset: a monument
which has collapsed into a void
West Littleton Churchyard: damage to the stone
surface caused by the corrosion of iron cramps. The
insert shows the extent of the corrosion through the
iron cramp and the resulting loss of stone.