Quickstart Guide to Lighting in Churches [From the book 'Treasures on Earth']
Atmosphere is vital to a church’s primary role as a place of worship, creating a feeling of comfort, wonder and anticipation. Lighting must be capable of encouraging this in private prayer and devotion, or in enlivening a large, joyous service. Architecture is an essential part of a church's existence. Architects throughout the ages have sought to worship God in their buildings; lighting must seek to underline this without taking over. Churches are used by young and old who are, increasingly nowadays, expected to take an active role in worship, singing, praying and reading the Bible. Lighting must enable the congregation, choir and clergy to see.
Lighting is a crucial element in the relationship of people to their churches. It affects the atmosphere in the church, it influences people’s appreciation of the architecture and it controls their ability to see. In the past, light was provided almost entirely by daylight with a small contribution from artificial sources such as candles. Churches were built to take maximum advantage of natural light and consequently often had a feeling of space or 'Mysterium Tremendum' (St. Augustine). They are frequently left in this state in the mistaken belief that they are as they were intended to be. Lighting is an area which has benefited from advances in technology and so is able to contribute to a church in a way which was not possible when many were built. This technology should be harnessed in order to improve people’s appreciation of churches, without harming the original intent of the builders, not only during daylight but also in periods of darkness when churches are at their most gloomy and forbidding.
This article will discuss the elements which create good and appropriate interior and exterior lighting and will indicate the equipment and techniques required by these elements.
The solution chosen to unite the three factors of atmosphere, architecture and visibility should be physically appropriate to the building and should combine them in a seamless fashion. The following elements can be used in building the solutions.
The choice of the solutions should start with a consideration of the lighting levels required throughout the building. There are two methods of quantifying lighting, one purely practical and one which attempts to quantify aesthetics.
The practical method identifies recommended illuminances with specific areas of a church. Illuminance is the measure, in lux, of the amount of light received on a surface. The level specified is usually the average level over the life of the installation, thereby incorporating losses due to accumulation of dirt and reduction of lamp output over life. The Chartered Institution of Building Services Engineers (CIBSE) SLL Code for Lighting recommends illuminances of 150 lux for the nave, chancel and vestries, and 300 lux for the pulpit, choir and organ.
Discretion can be used in the application of these levels, 100 lux may be acceptable for the body of a small country parish church while 300 lux may be more appropriate for a large pentecostal church, the decisions will be informed by the type of atmosphere required.
The alternative method of design, the 'apparent brightness method', permits an orderly calculation of the lighting needed to produce any proposed visual effect, this effect being specified by allotting relative brightness values to each surface in the interior, in arbitrary units.
Using apparent brightness scales, the reflectances of the surfaces, and inter-reflection calculations, it is possible to determine the relative direct illuminate needed on each major surface. Used fully this is a complex process which is most appropriate for large cathedrals, but in a restricted form it can be convenient as a method of specifying requirements.
Decorative lighting has historically been the major form of interior lighting. Since the advent of candles, through gas lighting to early electric lighting, the only source of lighting was a flame, or its equivalent, a bulb. This source needed disguising, especially in a building such as a church, to make it visually acceptable. In each period the design of decorative fittings was related to the architecture, but the essential function of the lamp has commonly been subordinated to the ornament and decoration of the fashions of the day. Decorative lighting remains one of the major elements today but it is increasingly being discredited due to the unfashionable appearance of many existing fittings and the difficulty of finding acceptable modern replacements.
Many churches are listed buildings or historical monuments in everyday use as a church. This means the lighting must fit the everyday use while being acceptable within an historic building. Much modern decorative lighting will not fit in this context; and it is necessary to incorporate modern lamp technology and lighting techniques into a decorative exterior appropriate to the period of the building and also to the modern design. It can be difficult and expensive to achieve but is well worth the trouble.
Existing decorative lighting should not be removed without careful consideration. In the case of nineteenth and twentieth century churches the light fittings might well form part of the original decorative scheme of the building; moreover, interiors can become lifeless when the focus is removed. The eye and brain respond to an apparent source of lighting enabling additional effects, described below, to be added without them being apparent.
Decorative fittings usually take the form of suspended luminaires, such as chandeliers, which can be designed to incorporate uplighting and downlighting as well as the normal ambient lighting. Care should be taken in the positioning of these luminaires to avoid blocking vistas, or views of specific objects, such as screens or stained glass windows. Wall brackets are less frequently used but can be useful, depending on the architectural period of the building. Consideration should be given to other forms of decorative lighting, such as the small luminaires commonly mounted on choir stalls or floor-mounted post luminaires which can be located in relation to seated areas or particular points of access.
Uplighting is increasingly used in churches both to provide illumination and to reveal the architecture. If used sensitively it can transform the interior by opening it out and creating a feeling of space, but if used badly it can unbalance the interior by creating a false focus on the roof. In commercial buildings uplighting is used as an indirect means of illumination, all the light is reflected off the ceiling, giving a soft lighting effect similar to daylight. To achieve this the ceiling necessarily becomes the brightest surface in view. While this can be successful in offices, it is frequently disastrous in churches. The illuminance levels needed on the pews require very high luminance levels on the roof. This can make the roof dominant in a way which is neither intended by the architect nor created by daylight.
When the illumination needed in the pews is provided by another source, uplighting can be used to reveal and accent the roof. The form and colour of the roof should be considered in choosing the source and position of the luminaire. Frequently the uplighting will be more successful if the luminaire is mounted high up, creating modelling on ribs and beams. Care should be taken to conceal the luminaires as much as possible or, if this is not possible, to ensure their location has a logic in terms of the building structure. Luminaires can look out of place if located in an apparently random fashion on the side walls of the nave. The aisles can also benefit from uplighting although their secondary importance in the architecture hierarchy should be respected.
Uplighting can benefit greatly from dimming, as discussed below, because as darkness falls the amount of lighting needed on the roof will be reduced. Depending on the window layout of the building it may be that bright uplighting will be beneficial in daylight, but that same level will be too bright at night.
Downlighting is vital in achieving the illumination levels needed in some parts of a church. It can be difficult, particularly in the nave, to obtain levels of 150 lux with just decorative and uplighting. Recessing the luminaires into the ceiling can be the most satisfactory solution, but this can usually only be done in modern buildings. It is important that the sources are well recessed in an optically-designed luminaire to avoid glare. One of the most successful installations of this type is in Sir Basil Spence’s Coventry Cathedral.
Where such a solution is not possible, typically in most old churches, the downlighting must be concealed within clerestory or triforium galleries, concealed within decorative luminaires or mounted visibly on side walls or column capitals. If the fittings are mounted on side walls it can be useful to combine the downlight with an uplight, possibly using the same source, thereby lessening clutter on the walls. In choosing or designing the luminaires care must be taken with louvring of the source to avoid glare to the congregation. This problem can often be alleviated by directing the light slightly towards the east end in the general direction of view towards the chancel or other major focus.
Downlighting on its own should be avoided because it creates disagreeable shadows on the faces of the congregation and clergy.
Church lighting does not always take the architecture into consideration. Sometimes this is justified because the building does not warrant it, but this oversight can be to the detriment of the atmosphere. It was suggested in the introduction that a church is not just a building where people gather to worship but also a building where people feel God’s presence in the atmosphere. This feeling can be accented and reaffirmed by revealing the architecture in a subtle way and by emphasising at night the accents created in daytime by daylight and sunlight.
The sources for this lighting should be concealed and the lighting levels will be critical in avoiding the danger of emphasising the building to the extent that is becomes the object of attention. Dimming can assist the creation of the optimum balance over different surfaces.
The combination of light and shade are the essential ingredients of this element. The form of the structure and the texture of the surfaces can be brought out by careful positioning of luminaires.
Spotlighting is important for adding focus and attention on top of the basic lighting. There are areas which will always benefit from additional spotlighting, for example the pulpit and lectern, the altar or communion table, a prominent crucifix or screen, important statues or wall plaques, or noticeboard areas. In many churches a more modern form of worship has evolved which involves the building of stages at the east end for drama and dance. Where this happens lighting of a theatrical form can be added, possibly with a separate control to enable it to be varied during services as appropriate. Even where the services do not use such theatrical techniques some spotlighting of the east end can be useful. It is important for the congregation to see the clergy, choir and others officiating at services. This lighting should be from the side and from the direction of the congregation, even though this will cause some glare for the clergy it will be of great benefit to the congregation.
Exterior lighting should reveal the architecture by night within the context of its surroundings. By day this happens naturally under daylight and sunlight but by night the building can die. It can be important for a church to look active as well as prominent and visible. Exterior lighting can do all this in a subtle manner without appearing garish or without being too dominant.
The lighting levels to be aimed for are not as easy to quantify as for interior lighting. The CIBSE Guide to The Exterior Environment recommends a series of average illuminances for floodlighting buildings. These range from 15 lux to 450 lux, depending on the ambient lighting conditions and the reflectance of the building surfaces, and have the objective of producing an acceptable level of overall building brightness.
The greatest mistake is to put too much lighting onto the building, thus washing it out. This commonly happens with discharge sources, where the lamps cannot be dimmed to achieve the desired levels. Site tests should be carried out to see exactly how the building will look within its surroundings.
Floodlighting has always been the common term for exterior lighting, suggesting that this is all that is involved. Much bad lighting has been created because the building has been flooded with light without any regard to its form or shape, with a result which may appear flat and shapeless. Floodlighting has its place and cannot be ignored, but it should be soft and subtle and, where appropriate, should underscore any building highlighting. If the luminaires are positioned carefully in relation to the building then structural details can be highlighted. Great care should be taken with floodlighting to avoid glare to passers-by.
Most churches are historic buildings with a wealth of detail. The lighting should always seek to emphasise this detail in all its variety. Modelling the building gives the opportunity to create a pattern of light and shade which should leave in obscurity the less prominent elements of the building. This highlighting should be achieved by the use of luminaires with specific optical control giving beams of light geared to the area of the building to be covered.
Many churches have particularly fine examples of stained glass windows which give great enjoyment when viewed from the inside against the sun. They can be equally attractive from the outside at night, if backlit from the inside. This backlighting can give life to a building and can add attractive and appropriate colour to the exterior view. Care will need to be taken to ensure that the effect of such lighting is not disturbing to those inside using the church, and to ensure that the luminaires are positioned in a manner sympathetic to the interior architecture.
The choice of luminaires is crucial to the success of the finished scene, a good lighting design can be ruined by inappropriate luminaires.
The choice of purely decorative luminaires has been discussed and will be very much governed by personal taste. The choice, however, of functional luminaires, whether floodlights or spotlights, can be very difficult. Once a lamp source and a desired beam spread had been chosen, consideration should be given to the form and bulk of the luminaire. It need not be of the period of the building, and usually cannot be, but it must sit sympathetically with the size, form and detail of the interior. Large industrial floodlights do not sit happily in a small medieval parish church, even if the light they give is exactly what is required. The finish and detailing should then be chosen to match or complement the material and style of the interior, for example, in old buildings with rough stone finishes a plain, natural metal finish can be very successful.
There is a large choice of luminaires from many different manufacturers, British, European and American and they are easy to obtain. If a luminaire of the ideal type and finish is not immediately obvious, keep looking; it is usually there. If the search continues to be fruitless then it is worth enquiring as to whether a manufacturer is willing to adapt or vary a standard luminaire; this is commonly done, and most manufacturers are only too happy to oblige. If this does not produce the desired result then recourse may be made to the design of special luminaires. Again, this is very common in the lighting industry and is frequently necessary for special buildings, such as churches. A reputable manufacturer should be sought and a clear agreement should be made at the beginning on what is required and to what standard the luminaires will be built.
Lighting and Conservation
It should always be borne in mind that light can have a detrimental effect on certain materials and objects displayed in churches. All organic material is at risk under light and it must be remembered that light can cause not only colour change but also deterioration in strength
Damage is caused by both visible and ultra-violet (UV) radiation. The likelihood of damage varies considerably according to the material concerned and increases the longer an object is exposed, and the more light to which it is exposed. Most damage caused both by visible and UV radiation comes from daylight, but artificial light can continue and aggravate the damage. It is rarely possible to treat the inside of a church like a museum and restrict light to a low level (around 50 lux) required by some fugitive materials so thought should be given to removing sensitive materials to a room where light can be strictly controlled. Care, however, should be taken to avoid unnecessary light on materials at risk.
The choice of the appropriate light source is vital to the proper creation of atmosphere. Unfortunately this is complicated by the fact that the question of finances comes into play. Few churches have spare resources, so the conservation of those resources is vital. Any lamp choice is a compromise between aesthetics and resources, a compromise which should be carefully made to avoid long-lasting errors.
The following list of lamp sources sets out what is currently available. Technology moves so fast that it cannot be up to date, expertise should be sought in this area.
- Tungsten and tungsten halogen
- Mains and low voltage reflector
- Mercury and metal halide discharge
- Tubular and compact fluorescent
- High pressure sodium discharge
Consideration of the luminaires is only part of the process when considering both aesthetics and resources. Aesthetically, individual luminaires are simply components in an overall picture created by the lighting. This overall picture, or lighting scene—a term used in lighting control to describe a combination of luminaires set at different levels—may only be one of several created to support different functions and activities in the church. There should be a method by which these lighting scenes can be reproduced accurately and easily. Frequently this is done by using a variety of switches. When the system is simple is will work well enough, but when many complex circuits are involved as in a large Cathedral, it may not prove satisfactory.
The ideal solution to this problem is the installation of a central control system, using contactors for discharge sources and dimmers for filament sources, with control points located at strategic points in the building. There are many systems available, both large and small, which enable the programming of different scenes to be recalled at the press of a button, or the touch of a panel. The selection of a scene will switch on the required discharge sources and fade the filament sources to the desired level. The dimming of filament sources is, perhaps, the most important tool in the creation of atmosphere by lighting. It allows the creation of a bright, happy atmosphere as well as a dim, solemn one. It allows the movement between different atmospheres in a subtle and imperceptible way. One of its more common uses is during a candlelit carol service, where change from darkness to bright lighting, via candle lighting, is required at different times during the service.
Financially, a central control system can be of enormous benefit, enabling a tight control to be kept on running costs. With the addition of a time-clock and a photocell, to read daylight, automatic scenes can be programmed to bring up or take out the lighting at set times or particular daylight levels. This is most useful for exterior lighting but may also have uses in interior lighting. When the system is mainly a dimming system for filament lighting large cost savings can be made. The act of dimming reduces the amount of energy used and can dramatically increase the life of the lamps. Filament lamp life may be extended to that of discharge lamps, showing savings in maintenance costs, due to the cheapness of filament lamps; this can offset the increased energy costs of the more aesthetically pleasing filament source lighting scenes.
Installation and Wiring
Electrical installation work, whether permanent or temporary, must be executed by competent electricians in accordance with the The IET Wiring Regulations, as published by the Institution of Engineering and Technology. These regulations are designed to ensure safety, especially from fire and electric shock. It is also important to snare that the electricians are familiar with the types of equipment involved and with the problems of working with, and in, church buildings. In addition the guidance note on Electrical Wiring Installations in Churches, published by the Church Buildings Council of the Church of England, should be consulted, particularly with regard to types of wiring, as well as other matters discussed in this chapter.
All luminaires and other equipment added to an existing building should be as unobtrusive as possible. Finishes and methods of fixing should be appropriate and sensitive to the building and great care should be taken to ensure that no fixings physically damage the structure. Wiring should be concealed or at least camouflaged and control equipment should be neatly houses, if possible in existing enclosures.
There follow notes on common types of wiring installation with comments as to their suitability.
Flexible cords: These are not recommended for any part of the permanent installation, and should be used only with fused 13 amp plugs or final connections to the luminaires.
Sheathed twin and earth: This is not recommended for any part of the permanent installation other than in areas which are totally concealed and protected; even in this situation its use should be avoided if possible, as it is too prone to damage.
Mineral insulated cable: This is the ideal method of installation, particularly in old churches where much of the installation needs to be surface run. It has excellent protection agains physical and fire damage.
Steel wire armoured: This is bulkier than mineral insulated calle and is thus less suitable for visible installations, but where the cable is not open to public view it is a good method of installation which has cost advantages over mineral insulated cable.
Plastic conduit: This is not recommended for aesthetic and safety reasons.
Metal conduit and trunking: This is a good method of installation where the installation cannot be seen and therefore aesthetics are not involved.
Lighting installations should be properly maintained so that they continue to be as effective as when they were first installed. Regular servicing will achieve this and will ensure long life for the equipment. Servicing should be planned and should ideally be carried out by a professional contractor, commonly an electrical contractor. If servicing is carried out by a men met of the staff or congregation it is important to ensure that they know what they are doing. The following servicing must be carried out.
Cleaning: Luminaires, windows and roof lights must be cleaned at appropriate intervals: depending on how clean the atmosphere is, exterior luminaires will need to be cleaned more frequently than interior.
Lamp changing: Lamps should be changed at regular, planned intervals, ideally after a period of use somewhat less than their rated life. If replacement is only carried out when lamps fail then labour costs will be higher and there is a greater chance of incorrect lamps being inserted because the correct ones were not available.
Electrical: The installation should be regularly inspected by an electrical contractor and any alterations or additions should be carried out using the same methods as the original installation.
Concept: A regular assessment of the suitability of the installation should be carried out to ensure that old and inefficient equipment or methods are not being unnecessarily perpetuated. Lighting technology makes substantial advances year by year, and advantage should be taken of them where they result in a more efficient or more effective lighting scheme.
It is unrealistic to expect that people not versed in the aesthetics and technology of lighting can take the information laid out in this article and use it to design successful lighting schemes. The information is intended to be a general guide to good practice in the field as well as a more specific guide to the assessment of existing schemes and the formulation of briefs for new schemes. It is important that both the laity and the clergy with a responsibility for looking after churches appreciate what is involved in lighting and what is or is not possible. They may then brief and work confidently with people who will actually design the lighting schemes, knowing that they will obtain the most appropriate result for their needs.
The difficulty for many churches is in choosing who will actually design the scheme. There are different ways this may be achieved but they are essentially split into two types, free and paid design.
Free design work is carried out by lighting manufacturers and suppliers, electrical contractors and members of the congregation. The manufacturers and suppliers design lighting schemes with the specific and understandable intention of selling their own equipment. The scheme may or may not be competent, or even good, but it is unlikely to be the best solution due to the limited range of equipment which that designer may have available. Contractors will design schemes in order to obtain the wiring contract but often they do not have detailed lighting skills. A member of the congregation must be judged on his merits, but it is a common mistake to allow an untrained person loose on a building because it is difficult to say no.
Paid design work puts the control in the hands of the church and the responsibility in the hands of the professional. Although at first sight it may seem an unnecessary expense, the benefits, in terms of quality and engineering, can more than repay this expenditure. Paid design work is carried out by lighting designers and consultants, architects and consulting electrical engineers. They all work professionally in their field and should have appropriate training and experience. It is important that before engaging a professional their previous work in the specialised field of church lighting is discussed. Architects and consulting engineers are more numerous and more frequently practice locally to a church but do not generally have the specialised skills of a lighting designer.