External Lighting2
External Lighting2
External Lighting2
cov1
CONTENTS
1 Introduction
1 6 Environment, security and dark skies 10
2 General considerations
2 Effects on the environment 10
Security 11
8 Glossary 12
3 Types of lighting
7 10 Useful Addresses 13
Lamp Data
9
The information in this publication is based on our current knowledge. The installation of an external lighting system implies in most cases the fixing of
Whilst every effort has been made to ensure the accuracy of the advice given, equipment to the fabric of a building. English Heritage seeks to ensure that any
English Heritage does not accept liability for loss or damage arising from the use works to a historic building do not disturb or destroy historic fabric.
of this information.This publication is intended as a general guide and should In deciding how best to illuminate a building, the principles of minimum
not be used as a substitute for professional advice intervention and reversibility should be adopted whenever and wherever possible.
FRONT COVER: Image showing a lit building situated along Grey Street, Newcastle
INTRODUCTION
Our historic buildings and monuments are often amazing feats of architecture and engineering.
Many have been enhanced and brought to life at night-time with striking and subtle external
lighting schemes. Some, however, have produced far more negative results by highlighting flaws and
views of the structure never meant to be seen. Just because a building or structure happens to
be listed does not mean this is a good enough reason to proceed with external lighting.
1
GENERAL CONSIDERATIONS 2ab Night and day views of Government House in Guernsey. Only the
architecturally important sections of the front elevation have been
illuminated. (Lighting design by Sutton Vane Associates)
Should the building be lit? 3a Backlighting used at Manchester Crematorium. (Photograph courtesy of
Lighting Architecture)
If a real demand for lighting has been established in 3b Uplighting used to illuminate Central Exchange Buildings, Grainger Town,
conjunction with the owners or custodians, then the Newcastle upon Tyne. (Lighting design by Sutton Vane Associates)
designer must look to limit the amount of light to that
strictly necessary to achieve the aims of the scheme. 2a
3a
2
4 Lighting to emphasise the pattern on a building. Where can external lights be positioned?
5abc Lights hidden from view in basement or lower pavement areas and
how they should be aimed. (Fig 5c courtesy of the Institution of It is essential that all luminaires are inconspicuous, easy
Lighting Engineers)
to install and maintain, and respectful of the historic
fabric. Even though a lighting design may give the
desired effect at night, if the floodlights cannot be
effectively hidden from view or disguised, the scheme
4 must be rethought.
5b
5a
5c
3
Are there any adjoining properties? Is light spilling 6a Remote light on a pole hidden by foliage.
from the surroundings? 6bc Remote light disguised by a street lantern. (6b Lighting design by Sutton
Vane Associates)
Neighbouring properties and the surrounding area must 7 Wildlife considerations.
be taken into account. In rural areas, with lower ambient
light levels with which to compete, less light will be
needed to floodlight a building.This is often overlooked in
6a
lighting scheme designs.This will reduce both the initial
outlay costs and ongoing energy consumption.
4
8a Soft lighting of a rural building. What is the most suitable light source?
8b Muncaster Castle, Cumbria. (Lighting design by Sutton Vane
Associates; photograph by Brian Sherwin)
The choice of light source must take into account the
colour and reflectivity of the building surfaces, the desired
colour rendering, the colour or operating temperature
of the lamps, and their effect on the building materials.
8a Street lighting designers have begun to move away from
high-pressure sodium (SON) lamps to metal halide (HIT)
lamps, which is to say from warmer, red tones to cooler,
blue tones of the colour spectrum. When choosing
floodlamps the designer must take into account both the
colour and the level of the local street lighting.
5
Are trials necessary? 9 All Saints Church, Newcastle upon Tyne. A lighting scheme employing
metal halide lamps against a background of high-pressure sodium
lighting. (Lighting design by Sutton Vane Associates)
The technicalities of colour rendering can be difficult to
10 Wide wash of light onto a building.
visualise, so it is often very useful to arrange a site
11ab Remote lighting locations using street furniture or other buildings.
demonstration of the options being considered.
11c Light mounted on a lamp-post; compare the cluttered effect here with
Photographs taken during the trial can be very useful Fig 6b. (Photograph courtesy of Sutton Vane Associates)
when applying for planning permission. 12 Dynamic lighting of The Monument, City of London.
13ab Illumination of selected elements of buildings.
With general historic environment and building stock,
consultation of the government’s Planning Policy Guidance
Notes (PPGs) – Planning Policy Guidance 15 (PPG 1994)
in particular – and their replacements, Planning Policy 9
Statements (PPSs), should be made.These documents
provide a framework and a useful reference to the overall
principles and requirements of the planning system. In
addition a proposal to externally light a building may need
planning permission under the Town and Country Planning
Act 1990, so early involvement of the local planning
authority is recommended as many aspects of the design
have the potential to be affected.
10 11a
6
11b
TYPES OF LIGHTING
We can break down most external lighting into three
basic types, each of which presents its own problems.
Architectural lighting
13a 13b
7
Dynamic lighting 14 Coloured lighting of a building.
15a Wellington Arch, London, for Breast Cancer Awareness Month, 2001.
(EH photo library K010791)
This choice makes use of theatre-style lighting fixtures
15b St Paul’s Cathedral for World Aids Day, 2002. (Lighting design by
to produce coloured light, moving patterns or Sutton Vane Associates)
projected images.
15a
15b
8
TYPES OF LIGHT SOURCES AND LEVELS TO USE
Listed below are the most commonly used light sources for external lighting.
Lamp data
Lamp type Colour appearance Colour Rendering Efficiency Rated life (hours)
Index Ra (sun=100) (lumens/watt)
Tubular fluorescent White 50–90 Good 15–70 Medium 6,000–10,000.
Compact fluorescent White 80 Good 25–80 Medium 10,000
Metal halide, warm White 65–80 Good 50–95 High 6,000–20,000
colour (also used in
fibre-optic systems)
Metal halide, cool White 65–90 Good 50–105 High 6,000–20,000
colour (also used in
fibre-optic systems)
High-pressure mercury White 40–50 Poor 25–55 Medium 12,000–24,000
Note: tungsten and tungsten halogen lamps have been excluded here: although these have excellent colour
rendering, lamp lives and efficiencies are very poor.
9
TYPES OF CONTROL SYSTEMS 16 Line drawings showing types of illumination
17 Useful light, spill light and light trespass. (Diagram courtesy of the
The control of an external lighting system does not Institution of Lighting Engineers)
10
(natural patterns of living and breeding). Light can also However it is not sky-gazers who are responsible for most
affect the feeding habitats of nocturnal hunting birds of the work that has been carried out to reduce light
(such as owls) and endanger other birds by disturbing pollution. It is, in the main, down to conservationists,
their sleep patterns (a false sunrise which confuses them individual residents and local communities.
into singing).
Artificial lighting has enabled us to do much more during Maintenance is less likely to be regular if access is difficult
the hours of darkness, but this freedom comes at a price. and expensive. If special equipment or personnel are
‘Light pollution’ is another term for sky glow, the needed to reach the light fittings, even replacing lamps or
brightening of the night sky caused by dust and aerosol cleaning will be prohibitive. However, ease of maintenance
particles of water in the air, which scatter any artificial may need to be reconciled with the need to hide or
light.This light comes from wasteful all-night shop disguise the luminaires.
advertising and display illumination, and from poor
external lighting schemes.
11
GLOSSARY BIBLIOGRAPHY
Column A pillar consisting of a base, a shaft and a capital, Atkins, Stephen 1991 The Influence of Street Lighting on
used to support or adorn a building. Crime and Fear of Crime (Crime Prevention Unit paper No
operating temperature of the lamp: the higher the operating Lighting for Urban Centres and Public Amenity Areas (British
Colour Rendering Index (Ra) The quantitative index – Ra, Chartered Institution of Building Services Engineers (CIBSE)
used to score the ability of a light source to render colours 1992 The Outdoor Environment (Lighting Guide LG6). London:
of surfaces accurately. For example Ra > 90 = accurate The Chartered Institution of Building Services Engineers
Colour spectrum (also known as the visible spectrum) The 2002 Code for Lighting. Oxford:
DIN rail (also known as Top-hat rail) A standardised, 2003 Environmental Considerations for External Lighting
35mm-wide metal rail with a hat-shaped cross section, used (Fact File No 7, Revision 1). London: CIBSE
Light-emitting diode (LED) A semiconductor device that Guidelines to Assist Parishes. Chelmsford: Diocesan Office
Luminaire A light fitting used to create artificial lighting or Electrical Contractors on Procedures Leading to the
Pattress A surface box or plate (in any shape to suit), with English Nature 2004 Bat Mitigation Guidelines: Working
fixing holes positioned to line up with architectural features, Today for Nature Tomorrow (Ref IN13.6). Peterborough:
Pediment A triangular element surmounting a portico, The role of lighting in the renaissance of historic urban areas’.
Portico A colonnade (roof supported by columns), or a Institution of Lighting Engineers (ILE) 1994 Lighting and
Projector A fitting capable of throwing a beam of light over International Commission on Illumination (CIE) 1993 Guide
Commission on Illumination
Shutter, baffle An adjustable device attached to a light fitting PPG 1994 Planning Policy Guidance 15: Planning and the
to eliminate light spillage and prevent glare.This often takes Historic Environment. London:The Stationery Office
12
Paterson, James and Mackness, Malcolm 2000 ‘How to do it Institution of Lighting Engineers
No 4: Church floodlighting’. Lighting Journal May/June 2000, Regent House
10–11 Regent Place
Rugby CV21 2PN
Ramsay, Malcolm 1991 The Effect of Better Street Lighting on Tel: 01788 576492
Crime and Fear: A Review (Crime Prevention Unit paper No www.ile.org.uk
29). London: Home Office Crime Prevention Unit
Natural England
Web-based reference material (Incorporating English Nature, the Countryside Agency and
the Rural Development Service)
Building Conservation Northminster House
www.buildingconservation.com
Peterborough PE1 1UA
Tel: 0845 600 3078
LightPollution.org
www.lightpollution.org.uk www.naturalengland.org.uk
ACKNOWLEDGEMENTS
USEFUL ADDRESSES English Heritage would like to acknowledge the help of the
following people in the production of this guide:
Catholic Bishops’ Conference of England and Wales
39 Eccleston Square Alan Anderson, Lighting Architecture
London SW1V 1BX
Tel: 020 7630 8220 Robert Bohannon, Sill Lighting UK
www.catholic-ew.org.uk
David Coatham, Institution of Lighting Engineers
The Chartered Institution of Building Services Engineers
222 Balham High Road Javis Gurr, English Heritage photo library
Balham
London SW12 9BS Steve Newbold, Electrical Contractors Association
Tel: 020 8675 5211
www.cibse.org Graham Smith, CES
HISTORIC ENVIRONMENT
HELM LOCAL MANAGEMENT www.helm.org.uk