Mechanical and electrical systems in architecture, engineering, and construction

961 Pages·23.619 MB·English

by  Dagostino, Frank R., Wujek, Joseph B

FIFTH EDITION
MECHANICAL AND
ELECTRICAL SYSTEMS
in Architecture,
Engineering, and
Construction
JOSEPH B. WUJEK
Advanced Building Consultants, LLC
FRANK R. DAGOSTINO
Prentice Hall
Upper Saddle River,New Jersey
Columbus,Ohio
Library of Congress Cataloging-in-Publication Data
Wujek, Joseph B.
Mechanical and electrical systems in architecture, engineering, and construction / Joseph B. Wujek, Frank
Dagostino. — 5th ed.
p. cm.
Rev. ed. of Mechanical and electrical systems in construction and architecture/ Frank Dagostino, Joseph B. Wujek.
ISBN-13: 978-0-13-500004-5
ISBN-10: 0-13-500004-1
1. Buildings––Mechanical equipment. 2. Buildings—Electric equipment. I. Dagostino, Frank R. II. Dagostino,
Frank R. Mechanical and electrical systems in construction and architecture. III. Title.
TH6010.D33 2010
696––dc22 2008053804
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A C K N O W L E D G M E N T S
This book is dedicated to my mother and father, Sophie and Purdue University; Bruce W. Smith, Auburn University; and
Joseph Wujek, Sr., and my family. The constant encouragement Russell Walters, University of Florida.
I received from my parents causes me to believe that anything The original author, the late Frank Dagostino, should be
is possible through hard work. I thankfully acknowledge my recognized because his insight and effort over many decades
best friend and wife, Shauna, for her patience, assistance, and served as a foundation for a fine book.
guidance. Mostly, I thank her for her love and companionship. I I am thankful to Sonya Kottcamp, Editorial Assistant,
also recognize my sons, Blaze and Bryce. They gave Dad the Eric Krassow, Acquisitions Editor, and Wanda Rockwell, Pro-
free time needed for the completion of a project of this size. duction Manager with Pearson Prentice Hall, who all worked
These commitments were all necessary in making this undertak- patiently and prudently to keep me on schedule (as best they
ing possible. could). Last, Evelyn Perricone, my copy editor, and Nitin
I am grateful to those students, faculty, professionals, col- Agarwal, my Project Manager, should also be recognized for
leagues, and others who have contributed to this work, either their hard work in turning my roughly written manuscript into
through direct contributions or through feedback. The many its present professional form.
professional associations and governmental entities that sup-
plied technical information in this book must be acknowledged.
Their cooperation and support are greatly appreciated. I thank Joseph Wujek
the following reviewers for their input: Daphene Cyr Koch,
iii
P R E F A C E
Mechanical and Electrical Systems in Architecture, Engineering, electrical technologies that are being incorporated into the
and Construction, fifth edition, is for those who must have a whole system that makes up an advanced building.
broad understanding of building mechanical and electrical Elementary engineering concepts and design principles
materials, equipment, and systems to successfully envision, are introduced in a straightforward manner. Over 150 new pho-
design, draw, construct, evaluate or operate a building or build- tographs and 40 new figures have been added to help improve
ing project. It is written specifically for those interested in build- the reader’s understanding of these subjects. Topics are pre-
ing heating, ventilating, and air conditioning (HVAC), plumbing sented on an intermediate mathematics level, requiring that the
and piping (water supply and sanitary drainage), storm drainage, student have a working knowledge of college algebra. Home-
illumination, electrical power distribution, building telecommu- work exercises and design problems are written with the intent
nications, acoustics and acoustical control, vertical/horizontal of introducing basic principles with, in most instances, real-
transportation and conveying, fire protection and suppression, world connections.
and building renewable energy and energy conservation systems. A text like this is needed because those in the architecture,
This book is intended to provide a broad-scope introduc- engineering, and construction (AEC) industry must have an un-
tion to building mechanical and electrical materials, equip- derstanding of whole building design. Building mechanical and
ment, systems, design concepts, and engineering principles. It electrical technologies are integral elements that make up the
presents material that can provide the future architect, archi- whole building system—that is, they are really elemental sys-
tectural engineer, and architectural engineering technician tems within a single system, each of which must function and
with a basic working-level knowledge of principles and practices. interact effectively with the other systems. Successful integra-
The audience of this text will likely be undergraduate college tion during design and construction depends on knowledge and
and university students in architecture, architectural technology, teamwork of all involved—the architectural designer, the me-
architectural engineering technology, construction engineering chanical and electrical engineer, the technician, the draftsperson,
technology, construction management, and elementary archi- the construction manager, the general contractor, the subcon-
tectural engineering. tractors, workers in the trades, and facilities managers and
The fifth edition of this book has been fully reformatted personnel. All involved should be familiar with basic design
and updated from the previous edition. This transformation is strategies, construction procedures, system characteristics, space
intended to better accommodate its use in introductory college requirements, and the time frame and progression at which such
and university courses. Nine chapters have been rewritten to work must be done on the job. Simply put, everyone involved in
reflect changes in the industry and the other chapters have been building design, construction, operation, maintenance, and de-
updated. Chapters on occupant transportation/conveying sys- construction should be familiar with building mechanical and
tems and emerging sustainability technologies have been added electrical systems.
to expand coverage. The new chapter, “Emerging Sustainable
Technologies,” addresses emerging building mechanical and Joseph Wujek
iv
P R O L O G U E
A general introduction to common building industry practices Mechanical and electrical systems in the building con-
and trends ensures that the reader has a basic understanding of struction industry fit within classifications known as mechanical/
the industry. Such an understanding is beneficial because it val- electrical/plumbing (MEP)or electrical/mechanical/plumbing/fire
idates the need for all building industry professionals to under- protection (E/M/P/FP)systems. MEP systems influence occu-
stand the subjects presented in this text: building mechanical pant health, comfort, and productivity, and greatly affect costs,
and electrical materials, components, equipment, and systems. including the first cost and operating (energy use and mainte-
This introduction is particularly helpful to the reader who has nance) costs. MEP systems are the heart and nervous system of
little or no experience in the building industry. a building.
THE BUILDING INDUSTRY ENVIRONMENTAL IMPACT OF BUILDINGS
The global architecture, engineering, and construction (AEC) The earth’s natural resources are limited and world population
industry accounts for about 10% of the world’s gross domestic continues to increase. With the passing of each day, there is a
product, 7% of all employment, and approximately half of all greater and greater reliance on natural resources and more
resource use, including about 40% of all energy consumption. degradation of the environment. Buildings account for a large
In the United States, the AEC industry is over a trillion dollar amount of resource (energy and water) consumption, land use,
business ($1069 trillion for construction alone in 2005). In 2005, atmospheric greenhouse gas emissions, and generation of envi-
the U.S. construction industry directly employed 7.3 million ronmental waste and pollution.
people and another 1.3 million people in architecture and engi- With about 4.5% of the world’s population, the United
neering. The AEC industry is big business in the United States States consumes nearly 23% of the total global energy. This
and worldwide. means that the U.S. consumes energy over 5 times the world
In the AEC industry, architectsand their support staff de- per capita average and over 100 times more per capita than
sign buildings, while engineers and their support staff design many undeveloped countries. The United States is not alone in
the engineering systems within these buildings. Constructors, its energy-use intensity. Countries like Qatar, Kuwait, Norway,
serving as contractors, and their employees and subcontractors and Canada use energy at a higher per capita rate. From a
build buildings. Construction managerssupervise the construc- global perspective, more developed, industrialized countries
tion project. Facilities managersand staff operate and maintain (e.g., countries in Europe, North America, Australia, New
buildings. All players must effectively work together as the Zealand, and Japan) make up only about 17% of the world’s
building design, construction, and operation team. population but use about three-quarters of the world’s energy
resources.
THE BUILDING MECHANICAL About 40% of the energy consumed in the United States
AND ELECTRICAL SYSTEMS is used in buildings. Thus, U.S. buildings use between 9 and
10% of the energy consumed worldwide. Of the energy con-
Well-designed, modern buildings are made up of many compo- sumed in U.S. buildings, about 40% is for space (comfort) heat-
nents and pieces of equipment that are integrated so that, when ing, cooling, and ventilation; about 18% is used for lighting; and
they are operated and maintained properly, they mutually per- almost 20% is used for domestic water heating. (See Tables P.1
form as a single system. Simply put, an efficient building system and P.2). About two-thirds of the electrical power produced is
is made up of many elemental systems. In buildings, mechanical consumed in buildings. In addition, U.S. buildings generate
and electrical technologies are among the most expensive and about 40% of the atmospheric emissions that make up green-
labor-intensive of these elemental systems. These mechanical house gases. Comparable magnitudes are used in most devel-
and electrical technologies are used for heating, ventilating, and oped European and Asian countries. As a result, MEP systems
air conditioning (HVAC), illumination, electrical power distribu- have a significant influence on global resource consumption and
tion, plumbing and piping (water supply and sanitary drainage), associated waste and pollution.
storm drainage, building telecommunications, acoustics and Developed and developing countries are totally dependent
acoustical control, vertical/horizontal transportation and convey- on natural (material and energy) resources. Many less developed
ing, fire protection and suppression, renewable energy sources, countries (e.g., countries in Africa, Asia [excluding Japan], re-
heat recovery, and energy conservation. gions of Melanesia, Micronesia, and Polynesia, Latin America,
v
vi PROLOGUE
TABLE P.1 RESIDENTIAL BUILDING ENERGY USE, vironment and human health by efficiently using resources (i.e.,
BY PERCENTAGE. energy, materials, and water), enhancing occupant health and
employee productivity, and eliminating or reducing waste and
End Use Single Family Multifamily
pollution. Reducing the amount of natural resources required in
constructing and operating buildings and the amount of pollu-
Space heating 52% 33%
tion generated by buildings is crucial for future sustainability. In
Appliances 22% 23%
Water heating 17% 32% buildings, this can be accomplished by effectively using materi-
Refrigerators 4% 6% als, increasing efficiency, and, developing and using new and re-
Space cooling 4% 5% newable energy technologies.
Dishwashers 1% 1%
Computed from data provided in U.S. DOE Commercial Buildings Energy
Consumption Survey (CBECS) 2003. MEP DESIGN AND LAYOUT
MEP components and equipment influence building design and
and the Caribbean) are striving to become more industrialized. layout. Dedicated building spaces or rooms must be reserved for
Many Asian countries (e.g., China, India, Taiwan, and South MEP components and equipment and serve as the nucleus of
Korea) and some Middle Eastern countries (e.g., Dubai, Qatar, these technologies. This can include, but is not limited to, cen-
and United Arab Emirates) are examples of countries experi- tral utility plants, boiler and chiller rooms, fuel rooms, electri-
encing rapid growth. These countries are becoming more cal switchboard rooms, transformer vaults, and metering and
resource-use intensive at a time when their rate of population communications closets. These spaces can make up a signifi-
growth is substantial. As developing countries move toward in- cant portion of a building floor area. Large commercial build-
dustrialization, resource use in these countries increases sub- ings have a single mechanical room of considerable size and
stantially, so that limited global resources are taxed more and often require additional rooms throughout the building. Sky-
will be exhausted sooner. A growing global population coupled scrapers may have mechanical spaces that occupy one or more
with ever increasing reliance on natural resources combines to complete floors. In contrast, a small commercial building or
create an outcome that is alarming. This concern makes a strong single-family residence may only have a small utility room.
case for integration of sustainable design practices in building The size of MEP rooms is typically tied to building occu-
MEP systems. pancy type and is usually proportional to the building size; that
is, hospitals and medical centers require more MEP space than
schools, offices, and residences. For example, in offices, depart-
SUSTAINABLE BUILDINGS ment stores, and schools, the MEP floor area is typically in the
range of about 3 to 8% of the gross floor area; in hospitals, it is
Sustainabilityis our ability to meet current needs without harm- about 7 to 15%; and in residences, it is typically less than 3%.
ing the environmental, economic, and societal systems on which Allowances must be made by the building designer to locate
future generations will rely for meeting their needs. It simply spaces near the habitable spaces, especially those spaces with
means using resources wisely. A sustainableor green building the largest demand for heating, cooling, power, and water (i.e.,
is designed to lessen the overall impact of a building on the en- kitchens, restrooms, bathrooms, and so forth).
TABLE P.2 COMMERCIAL BUILDING ENERGY USE, BY PERCENTAGE.
Health K–12 Colleges/
End Use Office Care Retail Schools Universities Governmental Lodging
Space heating 25% 23% 30% 45% 32% 36% 16%
Space cooling 9% 4% 10% 6% 5% 5% 6%
Ventilation 5% 3% 4% 2% 2% 3% 1%
Water heating 9% 28% 6% 19% 24% 17% 41%
Lighting 29% 16% 37% 19% 22% 21% 20%
Cooking 1% 5% 3% 2% 1% 2% 4%
Office equipment 16% 6% 4% 2% 2% 6% 3%
Refrigeration Negl. 2% 1% 1% 1% 2% 2%
Miscellaneous 5% 13% 5% 2% 11% 7% 6%
Computed from data provided in U.S. DOE Commercial Buildings Energy Consumption Survey (CBECS) 2003.
PROLOGUE vii
TABLE P.3 CHARACTERISTIC PERCENTAGE OF CONSTRUCTION AND COST BREAKDOWN OF
A 100 000 FT2OFFICE BUILDING PROJECT.
Percentage of
Division of Work Construction Cost Breakdown Description
General conditions 3% $ 750 000 General procedures, superintendent, trailer, fence,
traffic control, insurance
Site work 4% $ 1 000 000 Excavation/backfill, roads, walks, landscaping
Concrete 8% $ 2 000 000 Concrete foundations, framing, slabs
Masonry 7% $ 2 000 000 Concrete masonry, brick, stone, reinforcement, mortar, grout
Metals 11% $ 2 750 000 Structural steel framing, light-gauge framing
Woods and plastics 4% $ 1 000 000 Wood framing, millwork, cabinetry
Thermal/moisture protection 10% $ 2 500 000 Insulation, roof coverings, caulking, cladding
Doors and windows 8% $ 2 000 000 Doors, windows, glass, and glazing
Finishes 9% $ 2 250 000 Drywall, plaster, floor and ceiling coverings, paint
Specialties 4% $ 1 000 000 Signs, flagpoles, restroom accessories
Equipment 5% $ 1 250 000 Kitchen equipment, laboratory casework
Furnishings 4% $ 1 000 000 Artwork, furniture, room partitions
Special construction 3% $ 750 000 Computer rooms, clean rooms
Conveying systems 4% $ 1 000 000 Elevators, escalators, moving ramps, walkways
Mechanical 10% $ 2 500 000 HVAC, plumbing, fire protection
Electrical 6% $ 1 500 000 Power distribution, lighting, telecommunication
Total 100% $25 000 000 Complete project construction costs
ests of members who share a common field and promote profes-
MEP SYSTEM COSTS
sional and technical competence within the sustaining industry.
Professional organizations, frequently called societies, consist of
Design and construction costs of MEP components and equip- individuals of a common profession, whereas tradeassociations
ment are significant in buildings. Commercial and institutional consist of companies in a particular industry. However, the
buildings and large residences necessitate that an engineer de- distinction is not uniform; some professional associations
sign the MEP systems, whereas, in small residences, design is also accept certain corporate members, and conversely, trade
done by the mechanical and electrical trades. Design fees for associations may allow individual members. The activities of
MEP systems in commercial buildings typically range from 20 both trade and professional associations are similar and the ulti-
to 40% of the overall design costs, depending on building occu- mate goal is to promote, through cooperation, the economic ac-
pancy type and size. tivities of the members while maintaining ethical practices.
Actual MEP construction costs for buildings vary by Additionally, professional associations have the objectives of ex-
building occupancy type and construction method. In resi- panding the knowledge or skills of its members and writing pro-
dences and retail stores, the range is generally between 10 and fessional standards. Many governmental agenciesalso exist that
20% of the construction costs; for kindergarten through high support the work of these industries. Examples of professional,
schools (K–12), it ranges from 15 to 30%; for office and univer- trade, and governmental entities are provided in Table P.4.
sity classroom buildings, it ranges between 20 and 30%; and for
hospitals and medical centers, it is typically between 25 and
50%. A characteristic percentage of construction and cost CONSTRUCTION STANDARDS
breakdown of a commercial office building project is provided AND BUILDING CODES
in Table P.3. In this example, mechanical and electrical systems
(including conveying systems) account for 20% of the overall In the AEC industry, a standardis a set of specifications and de-
project construction costs. sign/construction techniques written by a standards writing
organization (see Table P.4) or group of industry professionals
that seek to standardize materials, components, equipment, or
MEP ASSOCIATIONS, SOCIETIES, methods of construction and operation. In the United States,
AND AGENCIES a building code is a law adopted by a state or is an ordinance
(a local law) approved by a local authority (a municipality or
Many professional associations and trade organizations support county) that establishes the minimum requirements for design,
the various MEP fields. Professional and trade associations are construction, use, renovation, alteration, and demolition of a
membership organizations, usually nonprofit, that serve the inter- building and its systems. The intent of a building code is to
viii PROLOGUE
TABLE P.4 EXAMPLES OF PROFESSIONAL SOCIETIES, TRADE ASSOCIATIONS, GOVERNMENTAL
AGENCIES, AND STANDARDS AND CODE-WRITING ENTITIES.
Professional Societies • U.S.Environmental Protection Association
• National Renewable Energy Laboratory
• American Institute of Architects
• American Society of Heating, Refrigerating and Air-Condition- Trade Associations
ing Engineers
• American Society of Mechanical Engineers • Air Conditioning Contractors of America
• American Society of Plumbing Engineers • Air Movement and Control Association
• American Society of Sanitary Engineering • Air-Conditioning and Refrigeration Institute
• Architectural Engineering Institute of the American Society of • American Boiler Manufacturers Association
Civil Engineers • American Gas Association
• Association of Energy Engineers • American Water Works Association
• Illuminating Engineering Society of North America • Construction Specifications Institute
• National Council of Acoustical Consultants • Gas Appliance Manufacturers Association
• National Society of Professional Engineers • Heating, Air Conditioning & Refrigeration Distributors Interna-
• Refrigeration Service Engineers Society tional
• Society of Fire Protection Engineers • Hydronic Heating Association
• Society of Women Engineers • International Telecommunications Union
• Mechanical Contractors Association of America
Standards and Code-Writing Entities • National Association of Electrical Distributors
• National Association of Home Builders
• American National Standards Institute
• National Association of Lighting Management
• American Society of Testing and Materials
Companies
• International Association of Plumbing and Mechanical Officials
• National Electrical Contractors Association
• International Code Council
• National Electrical Manufacturers Association
• International Fire Code Institute
• National Fire Protection Association
• National Fire Protection Association
• National Fire Sprinkler Association
• Underwriters Laboratories
• Plumbing-Heating-Cooling Contractors Association
• Sheet Metal and Air Conditioning Contractors’National Associ-
Governmental Agencies
ation
• National Institute of Building Sciences • U.S.Green Building Council
• U.S.Department of Energy
ensure health, safety, and welfare of the building occupants. model code to address local issues. Some states adopt a uniform
Building codes began as fire regulations written and enacted by statewide building code while others legally assign code adop-
several large cities during the 19th century, and have evolved tion to local authorities (counties and municipalities). Techni-
into a code that contains standards and specifications for mate- cally, a model building code is not a code (a law) until it is
rials, construction methods, structural strength, fire resistance, formally adopted. Model codes are periodically revised, usually
accessibility, egress (exiting), ventilation, illumination, energy every 3 to 5 years, to remain current with advancements and new
conservation, and other considerations. practices in industry. Each time a model code is revised, it needs
A model building code(i.e., International Building Code, to be reviewed and adopted into law by the governmental author-
National Electrical Code, and International Mechanical Code) is ity having jurisdiction (control). As a result, different code
a standardized document written by a standards writing organi- editions may be in effect in neighboring municipalities at a
zation (a group of professionals) and made available for adoption specific time, which can cause confusion that can lead to design/
by state and local jurisdictions. A municipality, county, or state construction errors. Professionals in the AEC industry must be-
may write its own building code, but typically it relies on adop- come familiar with and maintain a working-level understanding
tion of model codes as the base of its building code, mainly be- of current codes and standards, and must work hard to keep
cause it is easier. Amendments are usually made to the text of a abreast of revisions in each edition of the code.
C O N T E N T S
PREFACE iv Infrared Radiation,31
2.5 Transmission Heat Loss, 34
PROLOGUE v Thermal Conductivity, Conductance, and Resistance,34
Thermal Resistance of Air Films and Air Spaces,40
Chapter 1 THERMAL, ENVIRONMENTAL, Total Thermal Resistance,41
AND COMFORT CONCEPTS 1 Overall Coefficient of Heat Transmission,41
2.6 Thermal Bridging,44
1.1 Thermal Concepts,1
2.7 Transmission Heat Loss in Parallel Construction
Heat,1
Assemblies,47
Temperature,1
2.8 Temperature Gradient in Construction Assemblies,48
Density, 2
Study Questions, 49
Specific Heat,2
Specific Heat Capacity,3
Sensible and Latent Heating,4 Chapter 3 CONCEPTS IN BUILDING
Power,4 SCIENCE 53
1.2 Psychrometrics, 5 3.1 Building Science,53
Air,5 3.2 The Building,53
Psychrometric Variables,6 The Building Envelope,53
Psychrometric Chart,7 Embodied Energy,53
Using the Psychrometric Chart,9 Building Classifications,54
1.3 Factors Influencing Occupant Thermal Comfort, 12 Heating/Cooling Load Classifications,54
Body Temperature,12 Building Mass Classifications,56
Body Metabolism, 13 3.3 Thermal Insulation,57
Conditions of Thermal Comfort, 13 Characteristics of Thermal Insulation, 57
Environmental Factors Affecting Thermal Comfort,14 Types of Thermal Insulation,59
Occupant-Related Factors Affecting Thermal Insulating Techniques,60
Comfort,17 Superinsulation,63
1.4 Thermal Comfort,18 Thermal Storage, 63
Measuring Temperature and Relative Humidity,18 Mass and Effective Thermal Resistance,63
The Heat Index, 20 3.4 Windows,66
Wet Bulb Globe Temperature,21 Performance Measures, 66
Effective and Operative Temperatures,22 Types of Window Glazings, 67
Comfort Zones,22 Whole-Window Performance, 69
Overall Thermal Comfort in a Space,22 3.5 Thermal Testing, 69
Study Questions, 23 Thermographic Scanning, 69
Blower Door Testing, 69
Chapter 2 FUNDEMENTALS OF HEAT
3.6 Quality of Indoor Air, 70
TRANSFER 27 Indoor Air, 70
2.1 Modes of Heat Transfer,27 Indoor Air Quality, 70
Introduction,27 Indoor Air Contaminants, 71
Basic Theory,27 Biological Contaminants, 71
2.2 Conduction,27 Carbon Dioxide, 72
2.3 Convection,29 Environmental Tobacco Smoke, 73
Natural Convection,29 Combustion Pollutants, 73
Forced Convection,29 Ozone, 73
2.4 Radiation, 30 Volatile Organic Compounds (VOCs), 74
Ultraviolet Radiation,30 Airborne Lead, 74
Visible Light Radiation,31 Radon, 74
ix