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Moustafa M. Elsayed, Doha (12/9/2006) 1
What you need to know about Designing
Electro-Mechanical Systemsfor
High-Rise Buildings
By
Dr. Moustafa M. Elsayed
Moustafa M. Elsayed, Doha (12/9/2006) 2
Contents
• Definition of a High-Rise Building
• Introduction
• Design Requirements
• Stack Effect
• Core Design, Location and Components
• Floor-to-Floor Height & Raised Floor
Option
Moustafa M. Elsayed) 3
Contents
• Electric & Communication
Closets
• Building Orientation
• Insulation and Heat Stores
• Fire Scenario
• Fire Fighting Strategy
Moustafa M. Elsayed, Doha (12/9/2006) 4
Super High Rise
Building
Shimizu Super Highrise
(SSH)
Shimizu Corp. (Japan)
Moustafa M. Elsayed, Doha (12/9/2006) 6
Definition of a High-Rise Building
The International Building Code (IBC 2000)
and the Building Construction and Safety Code,
NFPA 5000TM-2002, define high-rise buildings
as:
A structure more than
22 m (75 feet ) high
Moustafa M. Elsayed, Doha (12/9/2006) 7
Definition of a High-Rise Building
A Strategy for Dublin Building Height, proposed four height thresholds
Low-rise - up
to 15m
Mid-rise - 5 to
50m
High-rise -
50 to 150m
Super high-
rise - above
150m
Moustafa M. Elsayed, Doha (12/9/2006) 8
Definition of a High-Rise Building
The ASHRAE Technical Committee for
Tall Buildings, TC 9.12
one whose height is greater than 300 feet
(91 m).
Moustafa M. Elsayed, Doha (12/9/2006) 9
Definition of a High-Rise Building
The Council on Tall
Buildings and Urban
Habitat (CTBUH)
one in which the
“tallness” strongly
influences planning
design or use.
Moustafa M. Elsayed, Doha (12/9/2006) 10
Definition of a High-Rise Building
The General Services Administration (GSA) in USA sponsored the “International Conference on Fire
Safety in High-Rise Buildings” in Warrenton, Virginia, on April 12, 1971. That conference arrived at
a more complex and more flexible definition that is appropriate. It stated:
A high-rise building is one in which emergency evacuation is not practical and in which fires must
be fought internally because of height.
Moustafa M. Elsayed, Doha (12/9/2006) 11
Introduction
The tall commercial
office building only
became possible
through the
invention of the
elevator safety
braking system by
Elisha Graves Otis in
1853.
Moustafa M. Elsayed, Doha (12/9/2006) 12
Introduction
• High-rise = high-risk
• All high-rise building design will require
performance-based (engineered) fire and
life safety design
• The fire resistance of the structure, to
larger and longer duration fires, will be a
consideration
Moustafa M. Elsayed, Doha (12/9/2006) 13
Introduction
• Every year there are about 7,000 fires that
break out in high rise office buildings
causing deaths, injuries and millions of
dollars in fire damage. Most of these could
be eliminated if everyone practiced good
fire prevention on the job and planned
ahead for a fire emergency.
• Construction material and fire proofing
material will get extra attention
Moustafa M. Elsayed, Doha (12/9/2006) 14
Design Requirements
Symbols of power, prestige, wealth,
success, and national pride.
Buildings, and their occupants, as safe and
secure as possible.
Moustafa M. Elsayed, Doha (12/9/2006) 15
Design Requirements
• Life safety
• Smart security
• More bandwidth, smarter buildings.
• More hours of operation, along with more
electrical capacity, fiber optic access, and
heating and air conditioning capacity.
• Energy efficient building
Moustafa M. Elsayed, Doha (12/9/2006) 16
Design Requirements
• Efficient vertical
transportation
• Smart mechanical systems
• Building infrastructure must
be well planned to attract
tenants
• Easy upgrades and retrofitting
to accommodate future
technologies.
Moustafa M. Elsayed, Doha (12/9/2006) 20
Stack Effect: Problems
Elevator doors’ failure to close
properly
Moustafa M. Elsayed, Doha (12/9/2006) 22
Stack Effect: Air Entry Points
• Entry doors & doors that
open to truck docks
• Any outside air intake or
exhaust
• Louvers that are provided in
the building
Moustafa M. Elsayed, Doha (12/9/2006) 23
Stack Effect: Air Entry Points
• Overhangs in the construction
with light fixtures that are located
immediately above the ground
level and are not properly sealed
against leakage.
• and any possible small fissures in
the exterior wall itself.
Moustafa M. Elsayed, Doha (12/9/2006) 24
Stack Effect: Internal Passages
• Fire stairs
• Elevator shafts
• Mechanical shafts for ducts and
piping
• Any other vertical penetrations
that exist at the edge of the
floor slab at the exterior wall or
for pipes.
Moustafa M. Elsayed, Doha (12/9/2006) 25
Means to Minimize Stack Effect
• Use tight exterior wall
• Vestibules or air locks for loading docks,
with good door seals, or use of revolving
doors
Minimizing Infiltration from Outside
Moustafa M. Elsayed, Doha (12/9/2006) 26
Minimizing Infiltration from Outside
• Use Supply at least 5% outside air than exhaust to ensure pressurization tight exterior wall
• Close all shafts & seal all penetrations
Moustafa M. Elsayed, Doha (12/9/2006) 27
Means to Minimize Stack Effect
Minimizing Internal Air Flow
Using doors at the
entry of elevator
banks
Stairs are to be
interrupted with
doors
Moustafa M. Elsayed, Doha (12/9/2006) 28
Core Design
•The core design should meet the
needs of the occupants while
also simplifying the provision of
mechanical and electrical
services to the occupied floor
•The cost of the core and its
content can be substantial.
Moustafa M. Elsayed, Doha (12/9/2006) 29
Core Design
• The configuration of the core should be
arranged in the tightest area possible,
resulting in the most efficient possible
use of the floor.
Moustafa M. Elsayed, Doha (12/9/2006) 30
Core Location
Central Core
• Maximum flexibility in the architectural
subdivision of the floor
• Potential to improve the distribution of air-
conditioning ducts
• Simplify the construction of the building
Moustafa M. Elsayed, Doha (12/9/2006) 31
Core Location
Multiple Cores
• In buildings with very large floor plates, multiple cores may be necessary to reduce the travel distance to stairs or toilets.
• A cost disadvantage of multiple cores is the potential need for additional elevators, although this is not always necessary.
Moustafa M. Elsayed, Doha (12/9/2006) 32
Core Components
• Fire stairs
• Vertical transportation elements: passenger
elevators and one or more service or freight
elevators
• Toilet rooms for both the male and female
• Electric closets
• Communication closets for multiple
telecommunication providers
Moustafa M. Elsayed, Doha (12/9/2006) 33
Core Components
• Local fan rooms or large supply air and
return air shafts
• Shaft space for other HVAC risers, such as
toilet exhaust, general exhaust, or dedicated
smoke exhaust risers and possibly kitchen
exhaust risers
Moustafa M. Elsayed, Doha (12/9/2006) 34
Core Components
• Space for risers for the piping of the HVAC
system and plumbing system as well as riser
space for electrical distribution cable and
distribution cable for the building
management and fire alarm systems.
Moustafa M. Elsayed, Doha (12/9/2006) 35
Core Area
• The definition of an efficient core is not simple in that the percentage of the gross area that will be used is very much a function of the size and the usage of the floor.
• For example, on larger floor plates, i.e., those with areas greater than 20,000 gross ft2 (1,800 gross m2), it is a core that often will take less than approximately 15 to 20 percent of the total floor area of a given floor.
Moustafa M. Elsayed, Doha (12/9/2006) 36
Core Area
• If a floor grows beyond a certain size or has
internal loads with high cooling requirements
it can become necessary to add a second local
floor air-handling unit and fan room, which
will cause a reduction in the usable area.
• Moreover, on smaller floor plates, the core
may take as much as 30 percent of the total
floor area.
Moustafa M. Elsayed, Doha (12/9/2006) 38
Floor-to-Floor Height
The overall cost of a tall building is affected by the floor-to-floor height of the individual floors.
Moustafa M. Elsayed, Doha (12/9/2006) 39
Floor-to-Floor Height
An increase in the floor-to-floor height will increase the surface area of the skin of the
building, the length of the vertical structural elements as well as all of the building’s other vertical elements, such as shaft enclosures,
HVAC, plumbing, electrical power distribution and telecommunication risers,
elevator components, stairs, and the length of the interior partitions.
Moustafa M. Elsayed, Doha (12/9/2006) 40
Floor-to-Floor Height
• Where zoning regulations exist that limit the bulk and height of a building, a small increase in the vertical dimension of each floor may result in fewer floors in the developed building.
• The final floor-to-floor height of the office occupancy floors of any building will involve decisions by the owner, architect, structural engineer, and both the HVAC and electrical engineers.
Moustafa M. Elsayed, Doha (12/9/2006) 41
Raised Floor Option
The need to satisfy the expanding and continually changing electronic needs in the
tall commercial building has forced consideration of the inclusion of a raised
floor to handle the horizontal distribution of both power wiring and information
technology cabling, which includes both the telecommunication cabling and any
interconnection of personal computers, printers, and the like.
Moustafa M. Elsayed, Doha (12/9/2006) 42
Raised Floor Option
Typically the raised floors in
general office occupancies will
be between 4 and 6 inches (100-
150 mm) above the concrete slab
when the raised floor is used
exclusively for the distribution
of power wiring and
information technology cabling.
Moustafa M. Elsayed, Doha (12/9/2006) 43
Raised Floor Option
• Floor tiles are included above the slab to provide the walking surface in the office space, which in turn are covered by carpet tiles of the same size as the floor tiles.
• The carpet tiles and then the floor tiles can easily be lifted to provide the needed access to allow modification of the wire and cable as changes evolve in the needs of tenants.
Moustafa M. Elsayed, Doha (12/9/2006) 44
Raised Floor Option
One cost benefit that resultes to projects using a
raised floor exclusively for wire and cable
distribution is that neither the wire nor the cable
installed within the raised floor cavity need be
plenum rated or installed in conduit.
Nonetheless, the application of raised floors with
under-the-floor air-conditioning distribution
systems is becoming more common with the
increased use of raised floors.
Moustafa M. Elsayed, Doha (12/9/2006) 45
Raised Floor Option
The use of a raised floor allows the
relocation of electric outlets and
information technology connections at a
relatively low cost when compared to the
cost of these relocations without a raised
floor.
Moustafa M. Elsayed, Doha (12/9/2006) 46
Raised Floor Option
The inclusion of the raised floor will increase
the floor-to-floor height, but the integration of
a raised floor with an under-floor air-
conditioning distribution system may
minimize, if not eliminate, the increase in the
floor-to-floor height for a given project.
Moustafa M. Elsayed, Doha (12/9/2006) 48
Floor-to-Floor Height: Conclusion
• The floor-to-floor height of a tall commercial office building can usually be of 3.8 m 4.1 m.
• See Figure 1-6.
• The space from the bottom of the ceiling to the top of the slab of the floor above is 1.2 m.
Moustafa M. Elsayed, Doha (12/9/2006) 49
Floor-to-Floor Height: Conclusion
• This 1.2 m space would contain the lighting fixtures, ducts, sprinkler piping, and structural steel system supporting the slab.
• An increase (or decrease) in any of the elements shown in this figure will result in an increase (or decrease) in the floor-to-floor height.
Moustafa M. Elsayed, Doha (12/9/2006) 50
Electric Closets
• Location: to permit diverse routing to any area of the floor to meet the design criterion, in watts per square foot.
• There are limits to the distance that the floor distribution cable can be extended on any given floor without a cost penalty.
Moustafa M. Elsayed, Doha (12/9/2006) 51
Electric Closets
• On a floor in excess of approximately 25,000 ft2 (2,400 m2), more than one electric closet will be required to serve that floor.
• On floors smaller than 25,000 ft2 (2,400 m2), a second closet may still be included to meet the possible future expansion needs
Moustafa M. Elsayed, Doha (12/9/2006) 52
Communication Closet• The communication closet has gone through
a major series of changes over the past decade.
• Originally the closet was called a telephone closet, but that terminology is rarely used today.
• The appropriate terminology is “telecommunication,” “communication,” or “information technology” closet.
Moustafa M. Elsayed, Doha (12/9/2006) 53
Communication Closet
• Traditionally, the closet contained the vertical telephone riser cables that in turn connected to telecommunication terminal blocks from which the horizontal runs on the specific floor were extended by the telephone company to the user’s phone.
• However, that was in a time when there was only one telephone company and no such thing as a computer.
Moustafa M. Elsayed, Doha (12/9/2006) 54
Communication Closet
The communication risers may not be installed
during construction, just the riser space and
empty sleeves in the communication closet,
with the empty risers being filled as specific
tenants request specific telecommunication
providers for their space.
Moustafa M. Elsayed, Doha (12/9/2006) 55
Communication Closet
In the below-grade levels, space will be
needed for multiple points of entry from each
telecommunication provider to allow its
service to be brought to two separate service
rooms from at least two different streets to
ensure continuity of service under any
possible emergency contingency.
Moustafa M. Elsayed, Doha (12/9/2006) 56
Building Orientation
• Tall buildings are exposed to
the full impact of external
temperatures and radiant
heat.
• The overall building
orientation has an important
bearing on energy
conservation.
Moustafa M. Elsayed, Doha (12/9/2006) 57
Insulation and heat stores
• Good thermal insulation of the building skin reduces heat transfer, both from solar gain and loss of coolness from the inside.
• A second skin (a rain wall) can be built over the inner wall with an air gap in between.
• Structural building mass may be used to store heat.
Moustafa M. Elsayed, Doha (12/9/2006) 58
Insulation and heat stores
• In temperate climates, structural and building mass can absorb solar heat during the day and release it at night. A water-spray system on hot facades promotes evaporation and therefore cooling.
• Also in temperate regions, solar windows or a solar-collector wall can be located on the outer face of the building to collect the sun's heat.
Moustafa M. Elsayed, Doha (12/9/2006) 59
Fire Scenario :
One Meridian Plaza Fire
• In 1991 a fire on the 22nd
floor of the 38-story Meridian
Bank Building (Philadelphia)
took place for more than 19
hours.
• It was the largest high-rise
office building fire in modern
American history
Moustafa M. Elsayed, Doha (12/9/2006) 60
Fire Scenario :
One Meridian Plaza Fire
• Completely consuming eight
floors of the building
• Fire was controlled only
when it reached a floor that
was protected by automatic
sprinklers.
Moustafa M. Elsayed, Doha (12/9/2006) 61
Fire Scenario : VENTING
• Sealed or locked windows (High-rise buildings may be considered windowless buildings)
• Risk of venting by breaking thick glass windows
Moustafa M. Elsayed, Doha (12/9/2006) 62
Fire Scenario : VENTING
• Large volumes of heat and
smoke generated by the
fire become trapped in the structure.
• This giant smoke cloud, spreads throughout the sealed high-rise building.
Moustafa M. Elsayed, Doha (12/9/2006) 63
Fire Scenario : Stack Effect
• The so-called "stack effect" causes smoke
to spread up or down many floors during
a fire in a high-rise.
• The uncontrollable smoke movement
caused by the stack effect is another
reason window venting is ineffective
during a high-rise fire.
Moustafa M. Elsayed, Doha (12/9/2006) 64
Fire Scenario : HVAC SYSTEMS
• HVAC systems in some HRB are not fire-resistive
• Ducts, shafts, and poke-through holes penetrate fire-resistive floors, walls, and ceilings
• A high-rise hotel fire in Las Vegas, Nevada, spread fire and smoke through the central air-conditioning system and killed 85 people in rooms on upper floors.
Moustafa M. Elsayed, Doha (12/9/2006) 65
Fire Scenario : HVAC SYSTEMS
• The air system was not equipped with smoke detectors arranged to shut down the system during an emergency.
• The fire dampers-shutters designed to stop spread of fire in ducts and shafts of the air-conditioning system--did not close properly.
Moustafa M. Elsayed, Doha (12/9/2006) 66
Fire Scenario : HVAC SYSTEMS
• Smoke, heat, and flame were pumped
throughout the so-called fire-resistive hotel by
the air-conditioning system.
• Firefighter's battling a fire in a high-rise
building depend on the building systems for
success in extinguishments.
Moustafa M. Elsayed, Doha (12/9/2006) 67
Fire Scenario : Service Systems
• The elevator system must take them, tools, and equipment up to the fire.
• The standpipe system must provide water pressure and volume to the upper floors.
Moustafa M. Elsayed, Doha (12/9/2006) 68
Fire Scenario : Service Systems
• A building communication system must
allow fire department firefighting radio
transmission in these steel skyscrapers.
• If any of these building systems fail or
are not present, firefighters will be
unable to extinguish the fire.
Moustafa M. Elsayed, Doha (12/9/2006) 69
Fire Scenario : Elevators
It is important to note that elevator shafts,
like stairwells, are vulnerable to smoke
contamination as well.
Moustafa M. Elsayed, Doha (12/9/2006) 70
Fire Scenario : Elevators
Due to both the Stack effect and the Breaking-of-the-Seal effect, smoke penetrates into both the elevator carriages and shafts during a fire. Additionally, when elevator carriages are forced to make stops on smoke filled floors, both the elevator shaft and the carriage itself can quickly become contaminated beyond usable limits.
Moustafa M. Elsayed, Doha (12/9/2006) 72
Fire Fighting Strategy
• At a low-rise building fire, strategy can be
to extinguish the fire and evacuate the
people at the same time.
• HRB people evacuation
• HRB defend in place strategy
Moustafa M. Elsayed, Doha (12/9/2006) 73
Impacts on Fire Engineering
• Performance of people trapped in a burning
high-rise building
• Firefighting strategies for HRB:
�from inside stairways.
�an interior attack.
Moustafa M. Elsayed, Doha (12/9/2006) 74
Impacts on Fire Engineering
• Firefighters must extinguish the fire using
handheld hose streams advanced through heat
and smoke from an inside stairway. If this
method fails, there is no alternate plan. An
outside attack is not an option.
Moustafa M. Elsayed, Doha (12/9/2006) 75
Fire Fighting Strategy
• A defend-in-place strategy depends on two factors: that the building has the ability to contain fire to a particular area and that the occupants will obey the fire chief's instruction to stay in place.
• Neither of these assumptions is necessarily true. High-rise buildings are not fire resistive, and people leave the high-rise buildings during a fire regardless of instructions to do otherwise.
• Experience showed that "the 'defend-in-place‘ strategy does not exist."
Moustafa M. Elsayed, Doha (12/9/2006) 76
Fire Fighting Strategy
• The only real fire protection for a high-rise
building is
�an automatic sprinkler
�a smoke-removal system
Moustafa M. Elsayed, Doha (12/9/2006) 77
Smoke Management: Objectives
• To remove smoke from the area within which a fire has developed
• To maintain smoke-free areas that will allow the occupants to exit the building without being subjected to the smoke generated by the fire.
Moustafa M. Elsayed, Doha (12/9/2006) 78
Methods of Smoke Control
Objectives
�To control the movement of smoke in case of
fire in order to facilitate the protection of the
occupants and properties in the building.
�To help firefighters to accomplish their job.
Moustafa M. Elsayed, Doha (12/9/2006) 79
Methods of Smoke Control
Compartmentation
Dilution
Pressurization
Moustafa M. Elsayed, Doha (12/9/2006) 80
Compartmentation
�Compartmentation is to use barriers with
sufficient evidence to remain effective
throughout a fire exposure. These barriers
provide protection against fire spread.
�Barriers like walls, partitions, floors, doors,
....etc, provide some level of smoke
protection to spaces remote from the fire
Methods of Smoke Control
Moustafa M. Elsayed, Doha (12/9/2006) 81
Dilution Remote from Fire
� This is used to maintain acceptable gas and
particulate concentrations in a compartment
subject to smoke infiltration from an
adjacent space.
� Dilution can be effective if the rate of smoke
leakage is small compared to either the total
volume of the safeguarded space or the rate
of purging air supplied to and removed from
the space.
Methods of Smoke Control
Moustafa M. Elsayed, Doha (12/9/2006) 82
Methods of Pressurization of
Stairwell
�To provide smoke-free
escape route in the event
of building fire
�To provide smoke-free
area for fire fighters.
Objectives
Moustafa M. Elsayed, Doha (12/9/2006) 87
Testing of Smoke Control Systems
Initial Testing
�To assure that the system is operated as
designed
� Possible problems :
�fans operate backward
�no electric power is supplied to fans
�controls do not work properly . . . etc.
Moustafa M. Elsayed, Doha (12/9/2006) 88
Testing of Smoke Control Systems
Regular Testing
� Measure pressure differences at
pressurization
� Measure air flow velocity from stairwell
through doors to various spaces
Moustafa M. Elsayed, Doha (12/9/2006) 90
Intrusion Detection System
• Some minimum requirements:
– Entrance to each office door
– Motion detection in each office
– Foyer motion detectors
– CCTV in each foyer, lobby, and parking area.
Moustafa M. Elsayed, Doha (12/9/2006) 91
Access Control System
Areas requiring medium level
access security will be controlled by the
access card, keypad with
memorized pass-number & fingerprint
verification.
Moustafa M. Elsayed, Doha (12/9/2006) 93
Card Reader BiometricsDoor Alarm
Live CameraFeeds
Card ReaderDatabase
Door AlarmDatabase
BiometricsDatabase
SmartCatchVision
Central Matrix Switch
ALERTS
RULES
Card Readersignal
Moustafa M. Elsayed, Doha (12/9/2006) 94
Security Guard Patrol System
• Conduct scheduled fire and security patrols.
• Guards patrol all floors throughout day and night.
• Record guards movements with access reader.
• May find problems with communications due to steel buildings.
• Can use intercom system
Moustafa M. Elsayed, Doha (12/9/2006) 95
Fire Control System
Fire Detection
&
Alarming
Automatic Fire
Fighting: Sprinklers
Moustafa M. Elsayed, Doha (12/9/2006) 96
Fire Alarm: Survivability Requirements
The Code requires that all circuits necessary for the operation of the
notification appliances be protected until they enter the evacuation signaling zone
that they serve. Any of the following methods meet the survivability
requirements:
• A two-hour rated cable or cable system
• A two-hour rated enclosure
• Performance alternatives approved by the Authority Having Jurisdiction.
Moustafa M. Elsayed, Doha (12/9/2006) 97
Emergency telephone stations are positioned at every floor throughout the
building to enable fire department personnel to communicate freely in their
fire fighting efforts.
The emergency phone system provides two-way communications throughout the
entire facility
Fire Alarm Fire Fighters
Telephone Systems
Moustafa M. Elsayed, Doha (12/9/2006) 98
This is to enables occupants to safely escape the building in the event of a power
failure.
This must be equipped with back up batteries capable of powering exit and
emergency lights for more than an hour
In high rise buildings emergency lights should be connected to the building fire
alarm system.
Emergency Lights
Moustafa M. Elsayed, Doha (12/9/2006) 99
Emergency Power
The building should have an emergency power generator.
Moustafa M. Elsayed, Doha (12/9/2006) 101
Air-Conditioning System Alternatives
• All-Air Variable Air Volume (VAV)
Systems
�Alternative types of VAV boxes
�Low Temperature Air VAV Systems
• Air-Water Systems
• Underfloor Air Systems
Moustafa M. Elsayed, Doha (12/9/2006) 104
Air Distribution Alternative Systems
Alternative 1
Central Fan Room
Alternative 2
Floor-by-Floor Fan Rooms with Chilled Water Units
Alternative 3
Floor-by-Floor Fan Rooms with Direct Expansion Units
Moustafa M. Elsayed, Doha (12/9/2006) 105
Alternative 1—Central Fan Room
• Multiple AHU systems in one or more
room
• Supply air delivered into a common
discharge header from all of the supply
systems
• Vertical risers in two-hour fire-rated
shafts within the core of the building
• At each floor: horizontal duct taps with a
fire damper
Moustafa M. Elsayed, Doha (12/9/2006) 106
Alternative 2—Floor-by-Floor Fan
Rooms with Chilled Water Units
A local floor fan room, located within building core
Chilled water for the cooling coil is provided by a central chilled water plant
Moustafa M. Elsayed, Doha (12/9/2006) 108
POINTS OF COMPARISON OF ALTERNATIVE SCHEMES
• First Cost
• Construction Schedule Impact
• Owner Issues
• Equipment Considerations
• Architectural Issues
Moustafa M. Elsayed, Doha (12/9/2006) 109
Central Heating and Cooling Plants
Design Factors
• Weight, space requirements, and impact on structural system.
• Effect on the construction schedule.
• Specific changes in mechanical room detailing and slab construction within which the equipment is located.
• Acoustical considerations.
Moustafa M. Elsayed, Doha (12/9/2006) 110
Central Heating and Cooling Plants
• Ease & cost of operation and
maintenance
• Available energy sources.
• Life-cycle costs of each alternative
solution
• Space and cost considerations of a long
vertical flue from the fossil-fueled boiler
Moustafa M. Elsayed, Doha (12/9/2006) 113
Acoustical Considerations
of Central Plant Locations
• Location of all equipment: allow achievement of desired acoustical levels in spaces above, below, or adjacent to central plants
• Solution will involve an understanding of characteristics of the sound generated by equipment and alternative paths
Moustafa M. Elsayed, Doha (12/9/2006) 114
Acoustical Considerations
of Central Plant Locations
Sound paths
• Transmission of noise itself through floors,
ceilings, and walls of mechanical space
• Vibration and noise associated with
vibration that is transmitted by building
structure to occupied areas
Moustafa M. Elsayed, Doha (12/9/2006) 116
Chilled Water Piping Arrangement:
Primary
&
Secondary Pumps
Moustafa M. Elsayed, Doha (12/9/2006) 117
Chillers Location
Virtually at any floor
Example:
70-storey, 900 foot
Open type expansion
Moustafa M. Elsayed, Doha (12/9/2006) 118
Chillers Location
Constrains
• Standard working pressure for chillers and heat
transfer equipment: 150 PSIG (1,000kPa).
• Additional cost for higher working pressure
(None proportional).
Moustafa M. Elsayed, Doha (12/9/2006) 119
Pressure Reduction: Alternative A
• Pump at discharge side of chiller
• Primary pumps & no secondary for chiller circuit
• Zone H.E. with secondary pumps
Moustafa M. Elsayed, Doha (12/9/2006) 120
Plate-and-frame H.E
The maximum head of each zone is 143 PSIG (986 kPa), which is below the threshold design pressure of 150 PSIG (1000kPa)
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The Economics Of Temperature Differentials
• Small buildings– a 10°F or 12°F DT in the chiller
– a 10°F DT or 3 gpm per ton for the condenser.
• HRB: capital costs of the piping, valves, and fittings can be substantially reduced, with a possible penalty in refrigeration machine operating cost, by using larger DT with a lower flow of water
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Conclusion
Higher DT in both the chiller and condenser is worthy of evaluation, as
there can be significant savings in cost of piping, fittings, and valves
The Economics Of Temperature Differentials
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Fire Safety Problem
A high-rise building is one in which emergency evacuation is not practical and in which fires
must be fought internally because of height
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Design of Life Safety Systems
• Architect
• Structure design engineer
• HVAC design engineer
• Electrical design engineer
• Fire fighting design
engineer
Moustafa M. Elsayed, Doha (12/9/2006) 125
Components of Fire Management System
• Detection system
• Fire standpipe and automatic sprinkler systems
• Smoke management system
• Emergency electric power system
• Automatic elevator recall system
• Communication and alarm notification systems
• Central fire command center.
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• In return air connection on each floor
• Downstream of filters in each supply system
• Ceiling of each elevator lobby
• Mechanical equipment rooms
• Transformer and telephone equipment rooms,
• Similar spaces unless room is protected by an automatic suppression system such as sprinklers.
Smoke Detectors Locations
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Definition of
Building Commissioning -1
Commissioning is a
quality assurance
process of
the installation of the
systems in a building.
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Definition of
Building Commissioning -2
• It is a process for achieving,
verifying and documenting the
performance of each system to
meet the operational needs of the
building within the capabilities of
the documented design and
specified equipment capacities,
according to the owner’s
functional criteria.
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Definition
of
Building
Commissioning -3
Successful
commissioning
includes the preparation
of manuals and training
of operation and
maintenance personnel
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The definition refers to the building as a total
system, which includes the structural elements, building envelope, life safety features, security systems, elevators,
escalators, plumbing, electrical, controls, and the HVAC.
Definition of
Building Commissioning - 4
Moustafa M. Elsayed, Doha (12/9/2006) 136
Advantages of Building
Commissioning
� Open channels of communication.
� Create a better understanding of design intent.
� Provide early assignment of performance responsibilities.
� Set performance goals such as energy, environment, and life cycle.
Moustafa M. Elsayed, Doha (12/9/2006) 137
Advantages of Building
Commissioning
�Establish continuous monitoring of priorities and schedules.
�Improve operation and maintenanceprograms.
�Improve quality of operator personnel training.
Moustafa M. Elsayed, Doha (12/9/2006) 138
Reduce callbacks
and assist in
dealing with
warranty claims.Enable owner to
recognize system
capabilities and
limitations
Advantages of Building
Commissioning
Moustafa M. Elsayed, Doha (12/9/2006) 139
Commissioning Team
� Commissioning authority
� ( qualified professional company or agency that implements the overall commissioning process )
� Owner
� Design professionals