passive house goes to work: western canada’s …...passive house for commercial office •private...
TRANSCRIPT
Passive House Goes to Work: Western Canada’s First Passive House Office Building
Presented by
GRAEME VERHULST – Waymark Architecture
1. IntroductiontoCharterTelecom• designbrief• location&climate
2. DesignChallengesandProcess• sitegeometry&constraints
3. ConstructionStatusandLessonsLearned4. Take-AwaysandRecommendations5. Questions
OVERVIEWPASSIVE HOUSE FOR COMMERCIAL OFFICE
• Privatedevelopment– build,hold,occupy,maintain• Notdrivenbytypicalbuild-to-leasepressures(LEED)
• Desirefor:• OccupantComfortandQualityWorkEnvironment• ResilienceandHighQualityofConstruction• ReducedOperatingCosts• …withoutmajorpremiumonconstructioncost
CLIENT’S MOTIVATIONPROJECT INTRODUCTION
• 2levelsoffice+1levelamenity/meeting/execsuites
• 16,186sqft[1,504sqm]grossfloorarea(FloorAreaRatiocalculation)
• 9,718sqf[902.8sqm]TFA(Passive HouseCalculation)
CONTEXTPROJECT INTRODUCTION
• BCEnergyCode:• ASHRAE90.1-2010or• (Canada)NECB• “Baselinevs.Proposed”
• BCEnergyStepCode• “NetZeroEnergyReady”by2032• AbsoluteMetrics:
• TEUI~PE• TEDI~Qh• Mandatoryenergymodel• Mandatoryairtightnesstesting
LOCAL CONVENTIONSPROJECT INTRODUCTION
• Langford,BC(GreaterVictoria,BC,Canada)• PacificNW- ClimateZone4(~2950HDD18ºCor5310HDD65ºF)
CLIMATEPROJECT INTRODUCTION
• Client• TechCompany;recentexpansion• Projectwillconsolidate55stafffrom2existinglocations
• Design&ConstructionTeam• somePHexperienced,othersnewtoPH
CLIENT AND TEAMPROJECT INTRODUCTION
• Narrow(20m)• Adjacentpropertiesexpectedtobedeveloped• Southelevation– primaryentranceandfrontage• Significanteastandwestexposures
SITE CONSTRAINTSPROJECT INTRODUCTION
• CommercialOfficePHinCanada– unique
• Externalclimateisheatingdominant
• MostlocalPHexamplesandexperienceregionallyareinsmallerandresidential-useprojects.
• Keydifference…?
COOLING DEMAND INTENSITYDESIGN CHALLENGES AND PROCESS
InternalGains!
BROAD STROKESPROJECT DESIGN
Ground Level2 Level3 Level4
BROAD STROKESDESIGN CHALLENGES AND PROCESS
BROAD STROKESDESIGN CHALLENGES AND PROCESS
SITE CONSTRAINTSPROJECT DESIGN
SITE CONSTRAINTSPROJECT DESIGN
• Conditionedvs.UnconditionedSpace• Elevatorlobbiesandstairsareoutsideofthermalbuildingenvelope
• Reducecomplexity,exposure,articulation,interfacewithunconditionedparking
• Transientoccupantsanyway
THERMAL ENVELOPE BOUNDARYDESIGN CHALLENGES AND PROCESS
SPACE PLANNING - PROGRAMDESIGN CHALLENGES AND PROCESS
SPACE PLANNING - SERVICESDESIGN CHALLENGES AND PROCESS
SPACE PLANNINGDESIGN CHALLENGES AND PROCESS
CONSTRUCTION SEQENCINGDESIGN CHALLENGES AND PROCESS
CONSTRUCTION SEQENCINGDESIGN CHALLENGES AND PROCESS
• Cross-LaminatedTimber(CLT)Construction
STRUCTURE AND PENETRATION COORDINATIONDESIGN CHALLENGES AND PROCESS
• MassTimberConstruction- Cross-LaminatedTimber(CLT)&Gluelam
STRUCTURE AND PENETRATION COORDINATIONDESIGN CHALLENGES AND PROCESS
• Onereasonwedidn’tgowithconcrete
STRUCTURE AND PENETRATION COORDINATIONDESIGN CHALLENGES AND PROCESS
• MassTimberConstruction- Cross-LaminatedTimber(CLT)&Gluelam
STRUCTURE AND PENETRATION COORDINATIONDESIGN CHALLENGES AND PROCESS
FINAL ENVELOPE SYSTEMDESIGN CHALLENGES AND PROCESS
STRUCTURALTRADESMEMBRANES&INSULATION
CLADDINGTRADES
FINAL ENVELOPE SYSTEMDESIGN CHALLENGES AND PROCESS
• TreatedFloorArea: 903sq m [9,718sqft]
• EnvelopeArea: 2025sq m [21,797sq ft]
• RatioTFA: Envelope 2.24
• WallInsulation U-value0.123to0.142 [R40to41]
• RoofInsulation(averageforslopedinsulation)U-value0.128 [R40]
PASSIVE HOUSE STATSDESIGN CHALLENGES AND PROCESS
• PassiveHouseCertificationCriteria:• Cooling+DehumidificationDemand<15kWh/m²-yr+dehum contribution
OR• CoolingLoad<10W/m²
MECHANICAL CONSIDERATIONSDESIGN CHALLENGES AND PROCESS
TypicalOfficeCoolingLoads…• SedentaryOfficeOccupant…
• 245BTU/h(71W)perperson• TypicalLighting…
• 0.7to1.1W/sqft• TypicalComputers“MediumDensity”…
• 1.0W/sqft• TypicalPhotocopier…
• 550W• TypicalCoffeeMachine…
• 1200BTU/h(350W)
10W/m²criteriabarelycoversofficelightingà unrealistictothiscriteriaforcommercialbuildings
• ComparisonofCoolingLoads:
COOLING DEMAND INTENSITYDESIGN CHALLENGES AND PROCESS
W/m² W/sqft sqft/ton
PassiveHouseCriteria 10 0.93 3778ASHRAEInternalGainsat:• 1.0W/sqft lighting• 1.0W/sqft equipment• 5people/1000sqft
25.4 2.36 1489
TypicalCommercialOfficeRuleofThumb 63 5.85 600
• ActualdesigncapacityforCharterTelecom18.5tonsover12,000sqft =650sqft/ton=58W/m²
3.PHPP+DynamicEnergyModeling– Design-Assistvs.ComplianceTool.Sophisticationofdesignsoftwaremustmeetcomplexityandscaleofbuilding.
TAKEAWAYS AND RECOMMENDATIONSCONCLUSIONS
• MissedOpportunitytoreduceCDIandPEusingNaturalVentilationandPassiveCooling
NATURAL VENTILATION AND PASSIVE COOLINGDESIGN CHALLENGES AND PROCESS
• Ventilation&EquipmentLimitations
• HRV-1– OfficeLevel1(2000CFM)• HRV-2– OfficeLevel2(2000CFM)• HRV-3– ExecutiveHospitalitySuites(200CFM)• HRV-4– Amenity/Meeting(1200CFM)
HVAC SYSTEM TYPE AND ZONINGDESIGN CHALLENGES AND PROCESS
• VariableRefrigerantVolume(VRV)System
HVAC SYSTEM TYPE AND ZONINGDESIGN CHALLENGES AND PROCESS
FOUNDATIONCONSTRUCTION STATUS & LESSONS LEARNED
CONCRETE TO WOODCONSTRUCTION STATUS & LESSONS LEARNED
ENGINEERED MASS TIMBERCONSTRUCTION STATUS & LESSONS LEARNED
ENGINEERED MASS TIMBERCONSTRUCTION STATUS & LESSONS LEARNED
ENGINEERED MASS TIMBERCONSTRUCTION STATUS & LESSONS LEARNED
AIR AND WEATHER BARRIERCONSTRUCTION STATUS & LESSONS LEARNED
WINDOWS & ROOF INSULATIONCONSTRUCTION STATUS & LESSONS LEARNED
INTERIORCONSTRUCTION STATUS & LESSONS LEARNED
• Framing/finishingcostssimilartoanyotherbuildingofthistype
COSTS Envelope CONSTRUCTION STATUS & LESSONS LEARNED
• Envelope~$22/sqft
• I-joist,insulation,airbarrier,WRB,rainscreen
• Someofthesecostsarenot“extra”,theyarejustdifferent
• Totalextraenvelopecostworksouttoabout$200,000
• $125KPlumbing($10/sqft)• $309KVRVHVACSystem($25/sqft)• $213KHRVs+SheetMetal($18/sqft)• $80KInsulation,Firestop,T.A.B.• TOTAL=approx $60/sqft
• Mechanicalison-parwithcomparablenon-PHoffice.
COSTS MechanicalCONSTRUCTION STATUS & LESSONS LEARNED
• TotalConstructionCost=$6.0MCAD(approx.~$375/grosssqft)
• VancouverIslandregionhasseenrecentsurgeinconstructioncosts,drivenbyrecentdemandforresidentialdevelopment.
• Stealofadealforasignaturebuilding.Representshigher-endrangeofClassAlow-riseofficeconstructionincludingfullinteriorfitout.
COSTS TOTALCONSTRUCTION STATUS & LESSONS LEARNED
1.PassiveHouseprinciplescanoffercomfort,quality,andvalueforprivatecommercialdevelopments.
TAKEAWAYS AND RECOMMENDATIONSCONCLUSIONS
2.Bewarecoolingrequirements.ConsideranEngineeredNaturalVentilationSystemifclimateallows.
TAKEAWAYS AND RECOMMENDATIONSCONCLUSIONS
• Ontrackforcertification
PASSIVE HOUSE CONSTRUCTION STATUS & LESSONS LEARNED
3.PHPP+DynamicEnergyModeling– Design-Assistvs.ComplianceTool.Sophisticationofdesignsoftwaremustmeetcomplexityandscaleofbuilding.
TAKEAWAYS AND RECOMMENDATIONSCONCLUSIONS
4.IntegratedDesignProcess- theonlywaytodesignandbuildPassiveHouseforareasonablecost
TAKEAWAYS AND RECOMMENDATIONSCONCLUSIONS
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