BCD Special Report on
Historic Churches
17th annual edition
21
systems should be considered. Tese fall
into three categories; intruder detection,
CCTV and physical protection.
Intruder detection
Where there is an active local community, the
sirens and fashing lights of an ordinary intruder
detection system should, once activated, be
sufcient to scare of most intruders. However,
where churches are remote or the community
in the immediate vicinity is disinterested, the
alarm will be ignored and the emboldened
thieves will take their chances. It is essential
that an alarm triggers a response as quickly
as possible but do be aware that if members
of the church are asked to fulfl this role, they
might be putting themselves at risk. Make sure
that there are strict procedures to investigate
safely and call the police for support. Where
budget allows, a company accredited by
the National Security Inspectorate (www.
nsi.org.uk) should be used to respond.
It is vital to minimise the risk of false
alarms. Te use of inappropriate devices can
lead to frequent false alarms, undermining
the credibility of the system and potentially
causing response to fall of to the point
where a genuine attack is likely to be
ignored, or the system is switched of.
Choosing the right type of
detection can be complicated:
• the confguration of most church roofs rules
out simple installations
• animals and environmental conditions can
cause false alarms
• more reliable systems are likely to require
more devices
• the appearance of some system components
is unlikely to be in keeping with a historic
church building
• if devices are positioned to suit the installer
rather than the specifc demands of the
site and its context, the system will be
compromised.
Tere is no universal answer, in each case
the system and the context must be carefully
considered to achieve the best outcomes. So,
what are the options? Te external passive
infrared detector (PIR) is probably the most
widely used because it is easily installed and
fexible in terms of the detection area it can
be set up to cover. Te problem is that the
detection area is often too wide and poorly
defned, and the PIR can also be triggered
by animals, sunlight and sometimes wind.
Nevertheless, PIR can be efective at protecting
small, specifc areas. One company (E-Bound
AVX Ltd) has also developed a system that
uses sequential confrmation to minimise
the risk of false alarms from roof areas. Tis
means that two devices looking at diferent
zones must be triggered to create a confrmed
alarm (the system therefore needs up to twice
the number of detectors). Tis approach is
standard in internal detection systems and
has dramatically reduced false alarm rates.
More reliable than PIR is the active infrared
detector (AIR). Tis consists of a transmitter
and receiver and a series of active infrared
light beams between them that, if interrupted,
triggers an alarm. As well as requiring twice
as many devices, these tend to be larger than
PIRs and need to be able to ‘see’ each other
(so difcult roof shapes create limitations).
Te cost of AIR is also signifcantly greater
than PIR. It is worth considering using a
combination of devices with AIR on long,
clear runs and PIR in difcult corners.
Buried cable or fence protection type
systems can also be adapted to protect lead
roofs. Tey use a variety of detection techniques
including vibration, pressure and electro-
magnetic pulses, each linked to software
analysers to eliminate false alarms from
weather or animals. Te cable, typically 5mm
in diameter, is laid in a continuous loop around
the roof, concentrating on vulnerable areas
to ensure there is sufcient cable to prevent
it being stepped over. It can be laid either on
or under the lead, depending on the detection
technology, and would be virtually invisible to
casual view and to the intruder. While such
systems ofer low false alarm rates, there is a
cost premium. Installation could cost as much
as a CCTV system, but some church roofs could
not accommodate CCTV for aesthetic reasons.
CCTV
To signifcantly improve protection, any of
the above technologies could be linked to
a CCTV system. Tis should be remotely
monitored, so that all activations can be
checked before contacting the police or a key-
holder. Te system could be linked to on-site
loudspeakers so that the operator can warn
the thieves that the police are on their way.
Te cost of installing sufcient detection
and surveillance equipment to monitor an
entire roof might well be beyond the dreams,
never mind the budget, of many small churches.
Nevertheless, it is no longer sufcient to
put up a few cameras and hope they have a
deterrent efect or will serve to identify lead
thieves: any captured images are likely to be
grainy and dark. Tey may show the thieves at
work, but they are unlikely to be sufcient to
identify the culprits and secure a conviction.
Tere is very little point installing cameras
in such circumstances without some form
of monitoring. Indeed, if the system and
response procedures are carefully thought
through, even low-budget internet-enabled
cameras have some potential when properly
monitored by members of the congregation.
One promising development is a system
called Wireless Watchman. Te system
incorporates detectors with cameras and
infrared lighting combined in a single unit,
a remote monitoring service and guard
response. Tis type of system uses the video
image to provide information about the alarm
activation, thus confrming an alarm, rather
than good quality images of the whole event.
Crucially, the theft is detected immediately,
and a response is despatched. Other similar
systems are available from other suppliers.
At some churches, particularly those
with a single access road, CCTV can be
used to survey the approaches, recording
the number plates of visiting vehicles rather
than peppering the entire church roof with
cameras. Te captured information could be
enough for police to trace known criminals.
One fnal point on CCTV; it is important
to be aware that images of people are covered
by the Data Protection Act, as is information
about people which is derived from images,
such as vehicle registration numbers. To
understand your responsibilities under the act,
see the CCTV Code of Practice (2008), which
is available on the website of the Information
Commissioner’s Ofce (www.ico.gov.uk).
In summary, poorly conceived alarm
systems will serve little if any purpose, and will
probably end up being switched of. However, a
carefully considered use of available technology
tailored to your church and the responses
you have available, should provide a reliable
system that helps to prevent lead theft.
Secure fixing
LedLok is a company that secures lead sheet
against theft using special fxings, which secure
the sheet to the roof but allow natural thermal
movement. Te specialist fxings and hidden
anti-theft bars are suitable for fat, pitched
and vertical surfaces, and they can be ftted
at any time to existing, new or replacement
roofs. After English Heritage expressed some
initial concerns about the appearance of the
fxings, the design was modifed and should be
acceptable in all but the most sensitive locations.
Alternatively, if sheet lead is being
replaced, consider having it fxed using
hollow rather than wood-core rolls. Te
copper fxings used to secure them make
the sheets more difcult to remove.
On its own, a signifcant barrier to
quick removal will frustrate thieves and
probably encourage them to look elsewhere.
But it is the combination of these measures
with surveillance or alarm systems that
gives the best chance that the thieves will
leave the site quickly, never to return.
Jon Livesey
is English Heritage’s national
security adviser. He trained as an architect
and worked in various practices in London
and Manchester before joining Greater
Manchester Police as an architectural liaison
ofcer, encouraging planners and architects
to proactively design out crime. He would like
to acknowledge the assistance of Ecclesiastical
Insurance Group and British Transport Police.
1 For more information on the history of lead
theft and eforts past and present to combat
it, see L Bennett, ‘Assets under attack:
metal theft, the built environment and the
dark side of the global recycling market’,
Environmental Law and Management, 20,
Shefeld Hallam University, 2008.
Te results of lead theft from the Grade I Ionic Temple
in the grounds of Chiswick House, London in June 2008