selected topics in high rise mechanical design
TRANSCRIPT
NORR | SWEGON ACADEMY
Toronto and Dubai Shangri-la Hotel
MAY 2010
SELECTED TOPICS IN HIGH RISE MECHANICAL DESIGN
Simcoe Towers
INTRODUCTION
Topic
A comparison of building mechanical practices in hot and cold climates. We will compare mechanical building design in urban Canada, (specifically Toronto and surrounding region) with the Middle East, (specifically Dubai and the GCC).
Thesis
There are many factors which influence building design choices not just climate.
Study Sample
Mid to high rise residential, hospitality and commercial facilities
INTRODUCTION
Toronto
Settled the 17th centuryCapital of the province of OntarioBusiness capital of CanadaSprawling metropolis on the north shore of Lake OntarioPopulation of 3.2 million Climate of 4 seasons
Schizophrenic summerGorgeous AutumnModerate winter with very cold periodsNon existent spring
Toronto Temperature Profile
-15.0-10.0-5.00.05.0
10.015.020.025.030.035.040.045.050.0
Jan
Feb
Mar Apr May Jun Ju
lAug Sep Oct NovDec
Month
Tem
pera
ture
(o C)
Temperature (°C ) Max.Temperature (°C ) MeanTemperature (°C ) Min.
INTRODUCTIONDubai
The business capital of the United Arab EmiratesTrade, Finance, Stocks & CommoditiesRegional travel hubTourist destinationRuled by Maktoum family since the 18th centuryArabian Gulf to the west Population of 1.3 million (mostly expatriates)Climate: two seasons:
Hot summers up to 50º C with high humidity. Spring and fall are more pleasant +/- 30º CWinter has lows of 15º C with occasional rain
Abu Dhabi Temperature Profile
-15.0-10.0
-5.00.05.0
10.015.020.025.030.035.040.045.050.0
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
Tem
pera
ture
(o C)
Temperature (°C ) Max.Temperature (°C ) MeanTemperature (°C ) Min.
INTRODUCTION
Why What How and Because
Why- SafetyHealthFit for purpose (meet comfort or process expectations)Economic viability (financial expectations, time)Effectiveness (Operations and Maintenance, energy efficiency, sustainability)
What - Movement of air, water etcunder the effects of gravity and powered delivery systems, subject to understood principles of heat transfer, fluid mechanics and solid mechanics
How - Achieve the Why with the What under the influences of
INTRODUCTION
How - Achieve the why with the what under the influences of:
BecauseClimateInternational standardsRegional regulationsInvestor/Developer expectationsLong term vs short term thinkingMarket forces• Vendors – availability in the market• Labour costs • Material costs• Contractor – habits, capabilitiesMaintenance likelihoodRegional habitTypes of ownershipEngineer’s position in the marketAesthetic and functional project goals including shape
INTRODUCTION
A building
10 Stories10 Stories 3.3 bar3.3 bar3.3 bar
INTRODUCTION
Some buildings
10 Stories10 Stories 10 Stories10 Stories10 Stories10 Stories
INTRODUCTION
A tall building
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
10 bar10 bar
INTRODUCTION
A taller building
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
INTRODUCTION
A taller building
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
10 Stories10 Stories
INTRODUCTION
In consideration of the foregoing we will examine the following mechanical design issues:
Plumbing Systems
Life Safety
Ventilation
Heating & Air Conditioning
PLUMBING SYSTEMS
Water Supply
TorontoRobust and developed infrastructureGenerally reliable 4 -6 barUp to 5 +/- stories no supplementary pumping is requiredMunicipality takes responsibility for water supply adequacy, quality, etc.
PLUMBING SYSTEMS
Water Supply
DubaiLegacy of unreliability, On site storage mandatoryRoof top tanks strongly incented
Concrete construction allows for extra weight of water
PLUMBING SYSTEMS
Water Supply
DubaiLegacy of unreliability, On site storage mandatoryRoof top tanks strongly incented
Concrete construction allows for extra weight of water
PLUMBING SYSTEMS
System pressure regulationEvery 30 stories of residential buildingResults in 10 bar additional pressure
Optimal delivery pressure of 1.5 – 2.5 bar Maximum 5 bar
Pressure regulation is necessary
PLUMBING SYSTEMS
Domestic Hot Water
Distributed tank type • electric• gas
Distributed tankless• gas• electric
Central supply• gas• electric
Dubai water chillingHot water from cold water tapsCold water from hot water taps
PLUMBING SYSTEMS
Domestic hot water recirculation in high rise
PLUMBING SYSTEMS
Drainage and Venting
Torontocomprehensive regulatory frameworkwell understood standard of practicevendors / designer/ authorities aligned
Dubairudimentary regulatory frameworkvarious international standards, BS, North American, EN, Chinesevendors / designers / authorities not well alignedVenting: not well understoodInstallation of traps and floor drains – habitDual stack mandatory
PLUMBING SYSTEMS
Tall building drainage
Hydraulic jump – lowest floors of a drainage riser must not be connected directly to the high building riser
LIFE SAFETY
NFPA National Fire Protection Associationcommon basis of designwidely acceptedcomprehensive standards on commercial, institutional and
industrial life safety issuesWater supply for fire fightingautomatic sprinkler systemfire hose system 4.5 bar residual pressure required
Torontolow rise building directly suppliedfire pumps supplied from back up emergency powerseparate sprinkler & standpipe pumps (usually)
Dubaialways pumpedelectric fire pump backed up by direct diesel driven fire pumpresults in combined sprinkler and fire standpipe systems
LIFE SAFETY
High Building Pressure Control – orifice plates
Application of sprinklers sometimes not well understood
Example: pendant sprinklers in exposed applications
Pendant sprinkler headsPendant sprinkler heads Upright sprinkler headUpright sprinkler head
LIFE SAFETY
Smoke Control
Smoke control specifically mandated for high buildingsDefinition of high building
Isolation of fire floorextraction from fire floorpressurize floor above and belowdifferential pressure of 12 Papressurize stairwell
Stairwell PressurizationMust supply at various points in the stairwell so that backpressure at exit doors is less than 133 N
VENTILATION
Fresh Air Supply
Toronto/Dubai: ASHRAE standards are a unifying normBoth Toronto and Dubai have months of the year when natural ventilation is not possible
Dubai ventilation shafts
Torontofiltered, heated, cooled, humidifiedheat recovery if dedicated fresh air system“FREE COOLING” when combined with system supply airdemand control just now starting to be utilized
Dubaisand trap, filtered, cooled, de-humidifiedheat recovery norm (mandatory)heat wheels, heat pipesconstant volume – demand control starting to be utilizedspace humidity is an issue
VENTILATION
Building Exhausts
Commercial kitchen exhaustsregulated under NFPA 96
grease fires are very dangerous
16 gauge welded duct in fire rated enclosure
Canadian authorities terminate 1.3 m above roof level
Special filtration technologies remove grease relaxes NFPA 96 requirements
VENTILATION
Building Exhausts
Residential Kitchen Exhaust
Residential Kitchen ExhaustNot regulated by NFPA 96UAE culturally inclined to fried foods
VENTILATION
Building Exhausts
Residential Kitchen Exhaust
Residential Kitchen ExhaustNot regulated by NFPA 96Culturally inclined to fried foodsSolution indirect central exhaust
VENTILATION
Washroom exhausts Central extraction is common in both Toronto and Dubai
Traditional regulations in Dubai required 2 m X 3 m open to air shafts at kitchens and bathrooms – planning nightmare. Exterior plumbing pipes and open to air ventilation.
Common Toronto high rise residential solution – individual toilet/kitchen extraction fans controlled from light switch, ducted directly outside. Brick façade can accept grilles even if Architects do not want these – low cost. Curtain wall solutions in Dubai cannot accommodate.
VENTILATION
High rise Residential Exhausts
Demand control extraction
KitchenBathroomLaundry
HEATING AND AIR CONDITIONING
Heating
ElectricDistributed hot waterDistributed gas
Tall Building hot water supply to:perimeter radiationoverhead radiationreheat of branch terminalsfan coil units
Dubai No heating
HEATING AND AIR CONDITIONING
Chilled Water SupplyToronto
Unitary equipment rather than Air cooled chillers
Water cooled chiller plants
HEATING AND AIR CONDITIONING
Chilled Water Supply
DubaiAir cooled chillersWater cooled chiller plantsDistrict cooling plants and distribution
HEATING AND AIR CONDITIONING
Air Conditioning Commercial Buildings
TorontoVAV • central• compartmentalizedConstant volume / variable
temperatureVariable volume / variable
temperature
Dubaisome VAVhorizontal fan coil units• installation complexity• maintenance issues• low floor space impact • improved floorplate efficiency• Meat locker effect
HEATING AND AIR CONDITIONING
Air Conditioning Residential and Hospitality
Torontohorizontal fan coilvertical fan coils
HEATING AND AIR CONDITIONING
Air Conditioning Residential and Hospitality
Dubaihorizontal fan coil units• installation complexity• maintenance issues• low floor space impact – improved
floorplate efficiency
SUMMARY
Toronto DubaiClimate cold winter harsh summerInternational standardsRegional regulationsInvestor/Developer expectations short term viewLong term vs short term thinkingMarket forces
• Vendors – position in the market• Labour – cost vs materials high labour costs low labour costs• Contractor – habits, capabilities• Maintenance likelihood moderate low
HabitType of ownership ownership not well defined
Engineer’s position in the marketArchitectural and functional goals
SUMMARY
Thank you for your attention
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