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ILLUSTRATED GUIDE to BUILDING SERVICES Comfort Systems Tom De Saulles

ILLUSTRATED GUIDE to BUILDING SERVICES Comfort Systems Tom De Saulles

SUPERSEDED by AG 15/2002

AN ILLUSTRATED GUIDE TO BUILDING SERVICES Comfort Systems Tom de Saulles

27/99 SUPERSEDED by AG 15/2002 27/99

AN ILLUSTRATED GUIDE TO BUILDING SERVICES Comfort Systems

Tom de Saulles

A Client’s Guide to Defining Building Engineering Services DETR ref. 39/3/426 (cc1648) BSRIA ref. SR 70290

The Building Services Research and Information Association Old Bracknell Lane West, Bracknell, Berkshire RG12 7AH Tel: +44 (0) 1344 426511 Fax: +44 (0) 1344 487575 e-mail: @bsria.co.uk web: www.bsria.co.uk SUPERSEDED by AG 15/2002

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means electronic, mechanical, photocopying, recording or otherwise without prior written permission of the publishers.

ISBN 0 86022 543 3 Printed by The Chameleon Press Ltd. BSRIA 70290 March 2000 SUPERSEDED by AG 15/2002 ACKNOWLEDGEMENTS

This work was part funded by the Department of the Environment, Transport and the Regions, under the ‘Partners in Innovation’ scheme. BSRIA acknowledges the financial support of the Department of the Environment, Transport and the Regions. BSRIA would also like to thank the Chartered Institution of Building Services Engineers (CIBSE) for their financial contribution.

The project was undertaken with the guidance of a steering group of industry representatives. BSRIA would like to thank the steering group for their help and guidance. The members of the group were:

Andrew Ford Fulcrum Consulting (Representing DETR) Dr Hywel Davies CIBSE (Representing CIBSE & CCF) John Killey Citibank (Representing CIBSE) John Deal CIBSE (Representing CIBSE) Nicholas Rowe Gardiner & Theobald (Representing BCO) Hans Haenlein Hans Haenlein Architects John Armstrong Ove Arup & Partners

Special acknowledgement is given to Gay Lawrence Race (BSRIA), for her considerable contribution to this publication.

BSRIA would also like to thank the following organisations who kindly provided the Clients’ photographs and additional information which have made this illustrated guide Forum (CCF) possible.

Airedale International Ltd Hudevad Ltd Ambi-Rad Limited Illuma Lighting Ltd Apollo Lighting Ltd Ledger Bennett Advertising Limited Atlantic 2000 Lightform Special Projects Limited Bluesky Communications Mitsubishi Electric Caradon Gent Limited Monodraught Limited Carrier Air Conditioning OSRAM Limited Clockwork Marketing Co Ltd Powrmatic Limited Colt International Ltd Royston Simpson Publicity Royal Institute of Covrad Limited Taylor Alden Limited British Architects (RIBA) Crompton Lighting Limited Temperature Limited Daikin Europe NV Toshiba Carrier UK Ltd DE-VI Electroheat Ltd Translite Systems Ltd Displacement Design Ltd Trox Technik BRITISH Dravo Environmental Services Ltd Trox (U.K.) Ltd FFwd Precision Marketing COUNCIL for The views expressed in this document are not necessarily those of the Secretary of OFFICES State for the Environment, Transport and the Regions. Final editorial control of this document rests with BSRIA.

BSRIA 27/99 An Illustrated Guide to Building Services SUPERSEDED by AG 15/2002 PREFACE

This illustrated guide provides basic reference information on building services systems for construction clients and professionals in other areas of the construction industry. The systems covered are:

· Heating · Ventilation · Air Conditioning · Lighting · Controls

For construction clients, the guide provides a simple insight into the main system options discussed during the briefing process and can consequently assist dialogue with the design team. It can also help clients to identify and raise technical questions which they feel are relevant to their organisation’s specific needs. For construction professionals, the guide provides a quick reference to building services systems and can assist their working knowledge of the subject.

To ensure the guide is simple and quick to use, a brief overview of each system is provided, followed by a list of key points. Photographs and simple drawings are used to help explain the appearance and operation of each system.

It is acknowledged that the design team’s role includes assessing and recommending appropriate design solutions for a given project. This guide makes no attempt to provide a route for system selection other than pointing out typical applications for many of the systems covered.

BSRIA 27/99 An Illustrated Guide to Building Services SUPERSEDED by AG 15/2002 CONTENTS PAGE GLOSSARY ii INTRODUCTION Introduction to building services 1 Building design and building services 2 Location of building services 3 4 HEATING 7 Convectors 8 8 Radiant heating 10 Warm air unit heaters 12 13 VENTILATION Natural ventilation - The use of windows 17 Natural ventilation - Powered window actuators 19 Natural ventilation - Single sided and cross ventilation 20 Natural ventilation - Stack ventilation 21 Natural ventilation - Stack/wind ventilators 22 Mechanical ventilation - extract only 23 Mechanical ventilation - supply only 24 Mechanical ventilation - supply and extract systems 25 AIR CONDITIONING Introduction to air conditioning systems 29 Constant volume (CV) 32 (VAV) 33 35 coils 36 Chilled beams 38 Chilled ceilings 39 Room based heat (Versatemp systems) 39 Split systems 40 Variable flow systems (VRF) 42 , dry coolers and cooling towers 43 Air diffusers 44 LIGHTING Light quality and lighting levels 47 Luminaires 48 Lighting systems for work areas 50 Lighting systems - design considerations and control systems 51 Summary of lamp characteristics 51 Standard incandescent lamps 53 Tungsten halogen lamps 54 Tubular fluorescent lamps 55 Compact fluorescent lamps 56 High pressure mercury lamps 57 Sodium lamps 58 Metal halide lamps 59 CONTROLS Introduction to control systems and components 63 Analogue and direct digital control (DCC) systems 65 Building management systems 66 Integrated control systems 67 ALPHABETICAL LIST OF SYSTEMS & EQUIPMENT 68

BSRIA 27/99 An Illustrated Guide to Building Services SUPERSEDED by AG 15/2002 This glossary contains largely non-technical explanations of common terms associated with building services and may differ in phraseology from definitions found in British Standards and GLOSSARY other authoritative sources. For detailed system and equipment descriptions use the alphabetical index at the back of the guide.

Air change rate The quantity of air supplied to a space, expressed in terms of the number of times the total volume of air in the space is replaced in a specific period of time, typically one hour.

Central plant The siting of plant items such as boilers, chillers air handling units etc. in a centralised plant room/area. Decentralised plant Plant items located at strategic points throughout the building, serving the local area. Downdraughts Downward moving draught caused by room air coming into contact with a cold surface in winter such as a window. The cool air sinks and can create a draught at low level. Emitters The means of getting the heat or cold from distribution systems into the individual space. Examples of emitters include radiators, convectors and radiant panels. Exhaust air Air which is exhausted to atmosphere. Extract air Stale air removed from a space. Some of this air may be re-circulated and some exhausted. False ceiling Suspended ceiling below the structural slab to give a void that can be used for services distribution, eg ventilation ductwork. Sometimes called the services zone. Cooling that can be obtained without operating chillers, eg by using outside air directly when it is at a low enough temperature. Glare Dazzle or excessive contrast which can make it difficult or dangerous to carry out a task. Discomfort glare causes visual discomfort without necessarily impairing the vision of the task or object eg glare caused by a very bright light in the field of view such as direct sunlight or an unshielded light bulb. Disability glare impairs the ability to see detail without necessarily causing discomfort eg glare caused by excessive dazzle or reflection such as light reflecting from a glossy surface or from water. High temperature Hot water circulated within a pressurised system at a temperature of more than 120oC. hot water (HTHW) Pressurisation is required to prevent the water turning to steam. (Medium temperature hot water (MTHW) operates between 90oC and 120oC) HVAC Heating, ventilation and air conditioning. Illuminance The amount of light reaching a surface such as a desk top. Measured in lux (one lumen per m2) eg 300 - 500 lux for a offices with visual display units (VDU). The quality of the internal air considering freshness, temperature, and pollutants. (IAQ) Infiltration Air that enters a building through cracks and gaps in the building fabric due to temperature difference and/or wind. This air can provide some ventilation but is uncontrolled and unreliable. Infiltration can also contribute to the building heat loss in winter and heat gain in summer. Low temperature Hot water circulated within a system under atmospheric pressure at a temperature of hot water (LTHW) usually less than 90oC Luminaire A fitting which houses one or more lamps and controls the distribution of light. An air handling luminaire is one through which room air is extracted. Lux Unit of illuminance. One lux is equal to one lumen per square metre. Mechanical services Term commonly used to describe heating, ventilation and air conditioning systems. Natural ventilation Ventilation air that enters a building by natural means ie due to temperature difference and/or wind. Noise rating (NR) European measure of sound level which relates to the sensitivity of the human ear. Often used to specify an acceptable sound level eg NR 35-40 for offices, NR 20 for a concert hall. Occupied zone The area of a space occupied by people - usually from floor level to a height of 1.8m. In spaces where the occupants are seated, such as an auditorium, the occupied zone will be smaller. Passive Systems or measures which achieve a reduction in the heating or cooling load without the systems/measures use of mechanical systems.

An Illustrated Guide to Building Services ii BSRIA 27/99 SUPERSEDED by AG 15/2002 This glossary contains largely non-technical explanations of common terms associated with building services and may differ in phraseology from definitions found in British Standards and GLOSSARY other authoritative sources. For detailed system and equipment descriptions use the alphabetical index at the back of the guide.

Plant Large items of machinery and apparatus. In the case of building services this term is usually used to describe major pieces of equipment such as boilers and chillers. Raised floor Raised floor above the structural floor slab to give a void that can be used for services distribution eg data cabling, small power etc. Re-circulation air Often more air is required to heat or cool than is needed to provide ventilation. The excess can sometimes be re-circulated providing a very effective method of heat recovery. Re- circulation may not possible when the air is contaminated with dangerous or unpleasant pollutants such as cigarette smoke. Relative humidity A term often used to specify the internal design condition for humidity within a space. A ratio, usually expressed as a percentage, indicating how humid the air is. Literally the actual vapour pressure of the air at a given dry bulb temperature divided by the saturation vapour pressure of the air at the same temperature. Resultant A temperature often used to specify a design condition for a space, it combines air temperature temperature, surface temperature and air velocity into a single index. Riser A shaft providing vertical distribution of services within a building ie to carry services between floors. Sealed building Building with non-openable windows. Solar gain Heat gain caused either by sunshine directly entering a space or by sunshine incident on building fabric which absorbs the heat and then transmits it to the space. Stratification A vertical temperature gradient in a fluid such as water or air caused by poor circulation. System An organised arrangement of plant and equipment that works together to provide a function such as heating or cooling. Terminal The end point of a system run. An air terminal device is the end point of a ductwork system, such as a or diffuser. Terminal unit A unit at the system outlet which usually provides local control eg a VAV terminal unit. Thermal response The time taken for a system or emitter to warm up eg how long it takes a to heat up. Also the time taken for the fabric of a building to respond to a change in temperature ie for the fabric to warm up or cool down. Ventilation Ventilation is primarily the supply of fresh air to a building to meet the needs of the occupants - to provide oxygen, dilute dioxide and odours to acceptable levels and remove contaminants. The stale (vitiated) air must also be extracted. Zoning The division of a building into a number of distinct zones for the purposes of system control (see introduction to air conditioning).

BSRIA 27/99 iii An Illustrated Guide to Building Services Introduction Heating VentilationSUPERSEDEDAir-conditioning by LightingAG 15/2002Controls

INTRODUCTION TO BUILDING SERVICES

What are building services? Building services, also sometimes called engineering services, are primarily used to help create a comfortable and safe living or working environment for people and processes, by providing warmth, light, water, power, sanitation, transport, communication, sound control, security and fire protection. There are a huge range of building services used in every building and also in many other places where a comfortable and usable internal environment must be created, such as ships, aircraft, trains etc.

For example: Houses have heating, ventilation, lighting, power, hot and cold water, drainage and telephone systems. They may also have alarm systems, fire protection or cooling. All these need to be controlled and to operate efficiently. Building services are not just for offices

More complex buildings and industrial processes may require many building services, which can amount to up to 50% of the total building cost - these can Why do I need to know about building services? include: When all building services are working well they tend to be ignored or taken for granted. When did you last visit a large · Heating, ventilation, air conditioning, public building and comment on how wonderful the heating · Daylighting and electrical lighting or lighting was? Building services play a huge part in · Electrical power services creating a successful building and are certainly the first · Acoustics - control of noise thing noticed when not working well - eg a flickering light or · Hot and cold water cold draughts. · Sanitation and drainage · Transport systems - lifts, elevators, document Building services engineering is a recognised specialist handling and mechanical conveyance discipline within the building process and building services · Communication systems - telephones, public engineers can provide design, installation, maintenance address, personal call systems etc and operation of building services systems. However some · Fire prevention and protection knowledge of building services is useful for everybody - we · Security systems all need to know how to operate systems - whether setting · Control for all these systems a or timeclock for the or · Special services - steam, medical gases, selecting a lamp to give a good light for reading. For those compressed air and vacuum services, waste involved in the design and operation of buildings it is disposal, kitchen services, dust and fume extract, essential to understand the role that services play in drying systems, vibration control, provision of creating a productive and comfortable environment, and to electricity supplies at various voltages and appreciate that there are now many choices available in frequencies etc systems and equipment that need to be assessed against individual priorities and needs.

Clients in particular need to be able to consider what conditions they want to achieve in their new or refurbished building, understand the system choices available and appreciate how the systems will need to be operated.

BSRIA 27/99 1 An Illustrated Guide to Building Serv ices Introduction Heating VentilationSUPERSEDEDAir-conditioning by LightingAG 15/2002Controls

INTRODUCTION - BUILDING DESIGN AND BUILDING SERVICES

Building design can determine many of the costs which an operator will encounter during the life of a building. The building services can account for around 28% of the capital cost and 50% of the operating cost for a typical office. It is therefore important that the services form an integral part of the overall building concept to help ensure they will operate efficiently. Involving the specialist building services engineer at an early stage in the design process can help achieve this objective.

If the services are not considered until a later stage, problems which could perhaps have been overcome by simple measures may require a more complex technical solution. A well designed building may cost a little more initially but the overall cost of ownership should be reduced. Whole life costs of building services systems should be considered as the cost- in-use element can form a large proportion of the total cost, outweighing the initial capital cost.

It is not always possible to design a building that can High internal heat gains and/or the need to have utilise all possible energy and environmentally friendly sealed windows to keep external noise/pollution out measures. Urban noise and pollution may dictate the means that some buildings cannot avoid the use of need for ‘sealed’ buildings incorporating a mechanical mechanical ventilation or air conditioning. ventilation or air conditioning system. The activities in some buildings can also necessitate air conditioning to offset a high internal heat gain.

Some basic energy efficient strategies relevant to most building types are:

· During cold weather useful heat gains should be maximised and heat losses minimised whilst ensuring adequate ventilation.

· Heat gains during warm weather should be minimised to avoid overheating. Correct orientation, external shading and fenestration can all reduce heat gains.

· Natural ventilation should be used wherever practicable. Deep plan depths and substantial partitioning can preclude this. Where natural ventilation alone is not adequate for cooling, a mixed mode system (combined natural and mechanical ventilation) may be sufficient as opposed to an air conditioning system.

· Where ever possible, maximum use of daylight should be made to reduce the energy used by artificial lighting. If internal heat gains are sufficiently low and the external environment is suitable, natural ventilation can provide a low energy solution to cooling and ventilating a building.

An Illustrated Guide to Building Services 2 BSRIA 27/99

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