passive house goes to work: western canada’s …...passive house for commercial office •private...

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

?