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External lightingfor historic buildings



CONTENTS

1 Introduction 1 10

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12

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2 General considerations

Should the building be lit?

Does the entire building need to be lit?

Is there a pattern or arrangement which should

be featured?

Where can external lights be positioned?

Are there any adjoining properties? Is light spilling

from the surroundings?

How big and how clean is the building?

Are there environmental matters to consider?

What is the most suitable light source?

How are illumination levels established?

Are trials necessary?

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3 Types of lighting

Conventional external lighting schemes

Architectural lighting

Dynamic lighting

4 Types of light sources and levels to use

Lamp Data

Available lumen intensities and distributions

5 Types of control systems

6 Environment, security and dark skies

Effects on the environment

Security

Dark skies

7 Installation and maintenance issues

8 Glossary

9 Bibliography

Web-based reference material

10 Useful Addresses

11 Acknowledgments

The information in this publication is based on our current knowledge.

Whilst every effort has been made to ensure the accuracy of the advice given,

English Heritage does not accept liability for loss or damage arising from the use

of this information.This publication is intended as a general guide and should

not be used as a substitute for professional advice

The inclusion in this publication of any company, group or individual, or any

product or service, should not be regarded as either a recommendation or

an endorsement by English Heritage or its agents.

The installation of an external lighting system implies in most cases the fixing of

equipment to the fabric of a building. English Heritage seeks to ensure that any

works to a historic building do not disturb or destroy historic fabric.

In deciding how best to illuminate a building, the principles of minimum

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 externallighting 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 tobe listed does not mean this is a good enough reason to proceed with external lighting.

1b

There are a number of matters that should be examined

before progressing with a design.The most important of

these is the question, ‘Has a real need to install lighting

been established?’ The next must be the acceptance that

a simply technical approach is useless.

The main objectives of external lighting should be:

● to promote observation and experience of the siteagainst the night sky

● to give the building an added dimension which will

enhance its key architectural elements as well as its

social and historical significance

● to improve the quality of the nocturnal environment

by promoting safety, ie avoidance of trip hazards

● to enhance night-time orientation and use, which

could potentially benefit the local economy

Therefore an aesthetic, as well as a technical, approach

is essential and will ultimately govern the result.

When external lighting is executed with a well-designed

and co-ordinated scheme using the correct choice

of equipment, the environmental impact, ie light

pollution and overspill, can be minimised and the energy

efficiency maximised.

1cSubtle external lighting when designed with care and

sensitivity can bring added life and scope to some of

our most treasured landmarks. It becomes an extension

to the architecture, improving the quality of the viewand complementing the structure’s shape, colouration

and form. It gives an added dynamic by bringing the

‘soul’ back into a place, and can be likened to ‘painting

with light’.

1a

1

1a Kingston upon Thames Bridge. (Photograph courtesy of Sill Lighting)

1b The Poseidon Fountain,Witley Court,Worcestershire.(EH photo library K971385)

1c Concentration of light on a prime local site.



3a

3b

2b

2a

2

GENERAL CONSIDERATIONS

Should the building be lit?

If a real demand for lighting has been established in

conjunction with the owners or custodians, then the

designer must look to limit the amount of light to that

strictly necessary to achieve the aims of the scheme.

Does the entire building need to be lit?

It is rarely necessary to light all the elevations of a

building, some parts often being unsuitable or inaccessible

for viewing. It is usually better to concentrate on the

prime nearby and distant night-time viewpoints. As part

of the design process distance, angle and position of the

viewer should always be taken into account.

Is there a pattern or arrangement which should

be featured?

It is often better to illuminate selected architectural and

sculptural features such as pediments, columns, porticos

or niches, rather than illuminating the whole building.

External lighting to reinforce a building’s patterns can

increase the appreciation of architectural details.

Crosslighting, uplighting and backlighting should all be

considered, although uplighting must be limited and

well controlled to avoid light pollution.

Designs can be refined by the use of tight beam

control; shutters or baffles can also help reduce

night-time light spill. However, the latter solution is

rarely acceptable in appearance during the day unless

the fittings can be concealed.

This leads to the next question.

2ab Night and day views of Government House in Guernsey. Only thearchitecturally important sections of the front elevation have beenilluminated. (Lighting design by Sutton Vane Associates)

3a Backlighting used at Manchester Crematorium. (Photograph courtesy of Lighting Architecture)

3b Uplighting used to illuminate Central Exchange Buildings, Grainger Town,Newcastle upon Tyne. (Lighting design by Sutton Vane Associates)



4

5a

5b

5c

Where can external lights be positioned?

It is essential that all luminaires are inconspicuous, easy

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

must be rethought.

One solution is to floodlight from a remote position.

Luminaires can be positioned on nearby buildings or

street furniture. Where there are trees and shrubs it

may be possible to disguise lighting poles.

3

4 Lighting to emphasise the pattern on a building.

5abc Lights hidden from view in basement or lower pavement areas andhow they should be aimed. (Fig 5c courtesy of the Institution of Lighting Engineers)



Are there any adjoining properties? Is light spilling

from the surroundings?

Neighbouring properties and the surrounding area must

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

lighting scheme designs.This will reduce both the initial

outlay costs and ongoing energy consumption.

How big and how clean is the building?

As well as the existing ambient lighting, the reflectivity of

the building surfaces must be taken into account.This will

be affected by the colour of the building materials, and

how clean they are.The more reflective a building, the

fewer luminaires will be needed and the less powerful

they will need to be.

Are there environmental matters to consider?

Lighting can affect some animals (for example bats and

owls) that make historic buildings their home. Some animals

and their habitats are protected by law.Where proposed

external lighting may affect such animals an impact

assessment will need to be made, taking into account

breeding, hibernation and points of egress and ingress. As

well as the increase in light levels, the effects of installation

and maintenance must also be taken into account.

6b

6a Remote light on a pole hidden by foliage.

6bc Remote light disguised by a street lantern. (6b Lighting design by SuttonVane Associates)

7 Wildlife considerations.

6a

4



8a

8b

What is the most suitable light source?

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.

Street lighting designers have begun to move away fromhigh-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.

To increase impact an interesting effect can usually be

achieved by using a lamp of a type different to that being

used for the existing lighting, and this can also reduce the

necessary number of luminaires and their power rating. If

there is any doubt as to which lamp should be chosen, then a small field trial will usually be enough to determine

the correct type.

How are illumination levels established?

The following publications provide standards and guidance:

● British Standards 1996 Road Lighting. Code of

Practice for Lighting for Urban Centres and Public

Amenity Areas (British Standard BS 5489-9:1996).

With simple examples of the calculation process

● Chartered Institution of Building Services

Engineers (CIBSE) 1992 The Outdoor Environment

(Lighting Guide LG6). London:The Chartered

Institution of Building Services Engineers. Includes

various lighting techniques

● International Commission on Illumination (CIE) 1993

Guide for Floodlighting (Publication 94).Vienna:

International Commission on Illumination

● Electrical Contractors Association (ECA)

Decorative Exterior Lighting of Churches. London:

Electrical Contractors Association. Includes

procedures for defining the most suitable type of

lamp and location based upon the type of building

material and its condition

● Institution of Lighting Engineers (ILE) 1994 Lighting

and Crime. Rugby: Institution of Lighting Engineers

5

8a Soft lighting of a rural building.

8b Muncaster Castle, Cumbria. (Lighting design by Sutton VaneAssociates; photograph by Brian Sherwin)



Are trials necessary?

The technicalities of colour rendering can be difficult to

visualise, so it is often very useful to arrange a site

demonstration of the options being considered.

Photographs taken during the trial can be very useful

when applying for planning permission.

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

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 designhave the potential to be affected.

When the building in question is a church that the parish

wishes to light, it is often worthwhile experimenting to

try and resolve as many problems as possible before

approaching the Diocesan Advisory Committee.The

committee will be concerned with all implications of

the design, including the financial costs (capital, running

and maintenance).

Where any historic property is within the environs of

an airpor t, development restrictions can apply, especially if the building comes within the airport’s public safety zone,

in which case additional early consultation will

be required.

11a10

9 All Saints Church, Newcastle upon Tyne. A lighting scheme employingmetal halide lamps against a background of high-pressure sodiumlighting. (Lighting design by Sutton Vane Associates)

10 Wide wash of light onto a building.

11ab Remote lighting locations using street furniture or other buildings.

11c Light mounted on a lamp-post; compare the cluttered effect here withFig 6b. (Photograph cour tesy of Sutton Vane Associates)

12 Dynamic lighting of The Monument, City of London.

13ab Illumination of selected elements of buildings.

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Dynamic lighting

This choice makes use of theatre-style lighting fixtures

to produce coloured light, moving patterns or

projected images.

Dynamic lighting has limited use, but where the building

is very plain and unadorned it can be pleasing for special occasions and celebrations. I should be stressed,

however, that a permanent dynamic display can quickly

become boring.

It is better to employ dynamic lighting for short periods of

time; good example are the pink floodlighting of London’s

Wellington Arch for Breast Cancer Awareness Month in

2001 (see Fig 15a) and its subsequent illumination with

images of falling poppies for the 80th anniversary of the

Royal British Legion. At Christmas time, the Amiens

Cathedral in France has a 45-minute light show whichcolours the façade as it would have been in medieval

times, painted and gilded, only this time with light.

15b

14

14 Coloured lighting of a building.

15a Wellington Arch, London, for Breast Cancer Awareness Month, 2001.(EH photo library K010791)

15b St Paul’s Cathedral for World Aids Day, 2002. (Lighting design by Sutton Vane Associates)

15a

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9

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

High-pressure sodium Yellow 25–60 Poor–medium 55–130 High 14,000–24,000

Low-pressure sodium Orange Not applicable 70–180 High 16,000

(monochromatic)

Light-emitting diodes White (also 70 White Good 7–10 Poor 50,000–70,000 (but can

(in array form) blue, amber, (although colour varies at present but be limited by driver life

green and red) between manufacturing improving to 20,000–50,000)

batches)

CDM (ceramic White 80–90 Good 70–95 High 6,000–9,000

discharge metal halide)

Note: tungsten and tungsten halogen lamps have been excluded here: although these have excellent colour

rendering, lamp lives and efficiencies are very poor.

Available lumen intensities and distributions

Type of illumination Peak intensity Light distribution Comments

(lumens)

Symmetrical beam 1000–2000 Beam width Popular due to low initial costs, but little(discharge lamps) real optical control

Symmetrical ‘projector’ 200–30,000 Beam width A useful tool if carefully applied

beam

Simple asymmetric 800–3,000 Beam width Popular due to light weight

beam

Asymmetric beam with 700–800 Beam width Gaining popularity due to good control

horizontal cut-off of upward light

Bulkhead lights 150 Light distribution Very wasteful unless used in confined space



TYPES OF CONTROL SYSTEMS

The control of an external lighting system does not

necessarily require anything more complicated than a

simple time switch or a photoelectric cell. Many schemes

only operate for a few hours of darkness (for example

until 23.00) to prevent unnecessary energy use. Electricity

bills are kept low, and the lighting causes much lessinterference with flora and fauna. Astronomers also

benefit from the reduced light pollution.

Round-pattern time switches (as they are often known)

come in a variety of ratings and types. Most provide

the user with on–off operation which tracks sunset

and sunrise times throughout the year, without the

need to sense light levels. An added facility allows the user

to select a fixed ‘off ’ time – say between 20.30

and 01.00 – and a fixed ‘on’ time. Switches can be

provided with a reserve battery, so that power outages donot affect operation.

Round-pattern switches give greater control than photo-

sensing devices, which must rely on the level of natural

light to operate, usually coming on at dusk and switching

off at dawn. On dark and cloudy days photoelectric

switches would be activated unnecessarily.

Time clocks can be retro-fitted as surface-mounted units,

or designed to be DIN rail – or panel-mounted to suit

the site.They are provided with openings and seals for

security to prevent possible tampering with the settings.

If more sophisticated operation is required, there are

proprietary control systems available, but these can be

expensive. For most straightforward external lighting

schemes, complex systems are unnecessary.

ENVIRONMENT, SECURITY AND DARK SKIES

This section looks in more detail at some of the issues

mentioned previously. Environment, security and dark skies(light pollution) are all important issues, each of concern

to different interest groups.

Effects on the environment

External lighting can be extremely disturbing to a variety

of plants and animals. Excessive light can have a dramatic

impact on the lives of nocturnal species such as bats, frogs,

lizards and birds by confusing their circadian rhythms

16

16 Line drawings showing types of illumination

17 Useful light, spill light and light trespass. (Diagram courtesy of theInstitution of Lighting Engineers)

17

10



(natural patterns of living and breeding). Light can also

affect the feeding habitats of nocturnal hunting birds

(such as owls) and endanger other birds by disturbing

their sleep patterns (a false sunrise which confuses them

into singing).

As well as animals, trees and nocturnal insects are

also affected. Normal seasonal variations may bedisturbed, affecting their interdependency and

associated ecosystems. Any reduction in numbers of

insects such as moths reduces the food supply of higher

birds and animals.

Security

‘More light equals less crime’ is often cited as a reason for

external lighting, but there is little hard evidence to

support this statement. Despite the popularity of external

lighting, crime rates have soared and published Home

Office statistical evidence indicates that the presence or

absence of light is of little or no importance.The fear of

crime can certainly be alleviated with good external

lighting, but poorly positioned or misdirected lights can

dazzle passers-by and create deeply shadowed areas

which hide cr iminal and anti-social activity.

Well-positioned luminaires will do more to deter criminals

than over-lighting. Passive infra-red sensors can give an

element of surprise to deter intruders outside the normal

operating times of the lighting system.

Dark skies

Artificial lighting has enabled us to do much more during

the hours of darkness, but this freedom comes at a price.

‘Light pollution’ is another term for sky glow, the

brightening of the night sky caused by dust and aerosol

particles of water in the air, which scatter any artificial

light.This light comes from wasteful all-night shop

advertising and display illumination, and from poor

external lighting schemes.

Light pollution prevents much of the population from

being able to enjoy the night sky. Sky glow now pollutes

nearly all of Britain’s night skies, interfering with

professional as well as amateur sky-gazers.

Simple spillage from a badly designed external lighting

scheme can cause a major nuisance to others, for example

by trespassing into a window and keeping occupants

awake.This is in addition to the wasted electricity and its

contribution to emissions of greenhouse gases.

However it is not sky-gazers who are responsible for most

of the work that has been carried out to reduce light

pollution. It is, in the main, down to conservationists,

individual residents and local communities.

INSTALLATION ANDMAINTENANCE ISSUES

Care in the installation of external lighting is doubly

important when it is actually fixed to the building. Such an

installation may require listed-building consent.Without

thoughtful consideration, light fittings may not only

disfigure the façade but their installation may also leave

permanent scars on the fabric.

The location of any luminaire should always take into

consideration the material onto which it is going to be

fixed.To avoid unnecessary destruction, fixings should be

drilled into joints rather than into stone and brick.Where

this is not feasible, pattresses should be used.

Maintenance is also important; without it the output and

safety of the final installation will be seriously jeopardized.

However, it is too often viewed as an unnecessary

expenditure and neglected. Neglect will inevitably result in

system failure, and is uneconomic in the long run. Lighting

maintenance should be scheduled into the building’s repair

and upkeep. Regular inspections should be made

(generally every 3–6 months) during which fittings arechecked and cleaned and any faulty luminaires and lamps

replaced. Reactive maintenance should be kept to a

minimum where possible.

Maintenance is less likely to be regular if access is difficult

and expensive. If special equipment or personnel are

needed to reach the light fittings, even replacing lamps or

cleaning will be prohibitive. However, ease of maintenance

may need to be reconciled with the need to hide or

disguise the luminaires.

11



Paterson, James and Mackness, Malcolm 2000 ‘How to do itNo 4: Church floodlighting’. Lighting Journal May/June 2000,10–11

Ramsay, Malcolm 1991 The Effect of Better Street Lighting onCrime and Fear: A Review (Crime Prevention Unit paper No

29). London: Home Office Crime Prevention Unit

Web-based reference material

Building Conservationwww.buildingconservation.com

LightPollution.orgwww.lightpollution.org.uk

Church Care (Church of England) www.churchcare.co.uk

USEFUL ADDRESSES

Catholic Bishops’ Conference of England and Wales39 Eccleston SquareLondon SW1V 1BXTel: 020 7630 8220www.catholic-ew.org.uk

The Chartered Institution of Building Services Engineers222 Balham High RoadBalhamLondon SW12 9BS

Tel: 020 8675 5211www.cibse.org

The Church of EnglandNational Church Institutions Administrative CentreChurch HouseGreat Smith Street Westminster London SW1P 3AZTel: 020 7898 1000www.cofe.anglican.org

Electrical Contractors Association

ESCA House34 Palace RoadLondon W2 4HYTel: 020 7221 7344www.eca.co.uk

English Heritage1 Waterhouse Square138–142 HolbornLondon EC1N 2STTel: 020 7973 3000www.english-heritage.org.uk

Institution of Lighting EngineersRegent HouseRegent PlaceRugby CV21 2PNTel: 01788 576492www.ile.org.uk

Natural England(Incorporating English Nature, the Countryside Agency and the Rural Development Service)Northminster HousePeterborough PE1 1UATel: 0845 600 3078www.naturalengland.org.uk

ACKNOWLEDGEMENTS

English Heritage would like to acknowledge the help of thefollowing people in the production of this guide:

Alan Anderson, Lighting Architecture

Robert Bohannon, Sill Lighting UK

David Coatham, Institution of Lighting Engineers

Javis Gurr, English Heritage photo librar y

Steve Newbold, Electrical Contractors Association

Graham Smith, CES

Mark Sutton Vane, Sutton Vane Associates

Text by Geraldine O’Farrell, English Heritage Building servicesEngineering and Safety Team (BEST)

Figures 1c, 4, 5a, 5b, 6a, 7, 8a, 10, 11a, 11b, 12, 13a, 13b, 14and 16 by Judith Dobie, Centre for Archaeology, EnglishHeritage

Edited by John King

Design and Production by Creative Services,English Heritage, 04/07

Printed by Vitesse (1000)

Product code 51330

April 2007

BACK COVER: Hoover Building at night, Perrivale, London 13

http://www.buildingconservation.com/

http://www.lightpollution.org.uk/

http://www.churchcare.co.uk/

http://www.catholic-ew.org.uk/

http://www.cibse.org/

http://www.cofe.anglican.org/

http://www.eca.co.uk/

http://www.english-heritage.org.uk/

http://www.ile.org.uk/

http://www.naturalengland.org.uk/

http://www.naturalengland.org.uk/

http://www.ile.org.uk/


http://www.eca.co.uk/

http://www.cofe.anglican.org/

http://www.cibse.org/

http://www.catholic-ew.org.uk/

http://www.churchcare.co.uk/

http://www.lightpollution.org.uk/

http://www.buildingconservation.com/



For copies of this leaflet, please contact English Heritage Customer Services

Department on 0870 333 1181 or email [email protected].

Published by English Heritage, April 2007. Product Code 51330. Copies are also

available on www.english-heritage.org.uk and www.helm.org.uk. Printed on

recycled paper containing 75% post-consumer waste.

mailto:[email protected]


http://www.helm.org.uk/

http://www.helm.org.uk/


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