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BUILDING COMMISSIONING:
The Value of Commissioning
CaGBC Building Advisor ProgramOctober, 2012John Kokko, P.Eng., CCP, LEED [email protected] x2424
LEARNING OBJECTIVES
What is building commissioning
What are the steps required by LEED
Why is it important What results can we expect
NEW BUILDING CX
LEED Credits
EAp1 – Fundamental Cx (Prerequisite)
Deals mainly with construction and getting the building operating before hand-over
EAc3 - Enhanced Cx (Credit) Deals with design and post occupancy operation
WHAT IS NEW BUILD COMMISSIONINGDefinition:
To bring a new project or facility on line
?
?
?
Hands over a
building that gives the owner what he paid for.
NAME FROM SHIP BUILDING
A commissioned ship is one deemed ready for service. Must pass several milestones. Equipment is installed and tested, problems are identified and
corrected, and staff are extensively trained. A commissioned ship is one whose materials, systems, and staff have
successfully completed a thorough quality assurance process. Commissioned ship is one ready to sail safely and reliably
VISION OF COMMISSIONINGTake the owner’s needs and wants► Ensure requirements properly articulated
Through the minds of the consultants► Ensure designs properly reflect OPR
Through the hands of suppliers and contractors► Ensure building is properly built
Deliver a properly performing building► Ensure all systems operate as intended
BUILDING Cx = QC FOR CARS? Similar to a QC
process for cars Note similarities in: Work area Tools Assembly
techniques Workers’
responsibilities
WHY IS COMMISSIONING NEEDED Don’t the design and construction teams already
do this? Everyone wants to do a good job. But two constrains:
1. Scope included with fees2. Knowledge of the state-of-the-art
Low price generally gets the job Designers responsible for code Site review for conformance to
drawings and specs Not performance beyond obvious
faults and complaints after the fact
UP-TO-DATE KNOWLEDGE Innovation moving extremely fast Innovative equipment and
systems are relatively unfamiliar to designers, contractors, operators and even manufacturers agents
Energy efficiency, integrated systems, imported design concepts and computerization have multiplied levels of complexity
WHAT IS INNOVATIONMULTIPLE MARRIED TECHNOLOGIES
ADDED COMPLICATIONS
Radiant heating Radiant cooling Condensing boiler Water-side economizer Building automation systems
INNOVATION INCREASING EXPONENTIALLY
Direct and indirect evaporative coolingOptimum startCascading PID loopsStratified thermal storageDaylighting controlLON and BACnetIntegration
And on and on and on ….
CONVENTIONAL COMMISSIONING
• Start-up and basic check out of equipment• Testing, Adjusting and Balancing (TAB)• Begins after systems in and ready for
start-up• Verify individual components function as
components• Performed by installing contractor or
manufacturers rep
TOTAL COMMISSIONING (LEED™)
A systematic quality assurance program
Starts at concept design and concludes at end of warranty
Includes all phases concept design, detailed design, construction, start-up, 1 year operation
Commissioning verifies energy performance and comfort maintenance
TOTAL COMMISSIONING (LEED™)
Includes reviews through all stages Includes participation of consultants, trades,
O&M staff Includes detailed reviews design, shop draw, install Expanded installation verification and start-up checks O&M documentation more centralized Whole system performance vs. component checks
COMMISSIONING COMPARISONTOTAL COMMISSIONING
Concept Design ReviewsDetailed Design ReviewsShop Drawing ReviewsSite Installation VerificationEquipment Start-Up Verification
Balancing VerificationFunctional Performance TestDocumentation and Operator
TrainingTrending and Seasonal FPTWarranty and Occupant
concerns
TRADITIONAL COMMISSIONING
No Cx. Consultant self-checks. No Cx. Consultant self-checks. No Cx. Dwgs & specs met only. No Cx. Dwgs & specs met only. Contractor or Manufacturer only. No
systems interoperability
No Cx. Contractor self-checks.No Cx. Contractor self-checks.No Cx. Contractor self-checks.
Owner verifies acceptability.Contractor seldom returnsNo Cx. Respond to complaints only.
VALUE OF Cx
Largest study to date Mills, LBNL July 2009 http://cx.lbl.gov/2009-assessment.html 643 buildings, 26 US states 561 existing and 82 new buildings 37 Cx firms 99 M ft2, $2.2 B construct 90.4 M ft2 existing, 8.8 M ft2 new construction $43 M Cx costs
NEW BUILDING Cx MEDIANS
Cx cost, $1.16/ft2 or 0.4% of overall construct cost ($290/ft2) (Range $0.60 - $2.15)
Number of deficiencies identified, 3,528(about 1/3 of projects reported deficiencies)
Energy savings 13% (Range 9% - 29%) Payback time, 4.2 years (Range 1.7 to 11.4 yrs)
AREAS OF BENEFIT
Construction Cost Savings Equipment downsizing and trade-offs
Energy Savings - $0.05 to $0.45/ft2 Peak demand reductions Maintenance and replacement costs reduced Increased productivity and reduced liability
Indoor environmental quality maintenance
Carbon emissions reductions
COMMISSIONING PROCESS OVERVIEW
LEED Cx OUTLINEDesign and Construction Phases EAp1 – Fundamental Cx EAc3 – Enhanced Cx
Design Owner documents OPR Before 50% CD Owner designatesCxA
Construction Documents Designers incorporate Cx specs into Construction Docs
CxA presents Cx Plan
50% CD CxA conducts 50% design review
Post Contract Award Owner designates CxACxA presents Cx Plan
CxA reviews shop drawings
Installation CxA performs/oversees installation verification
Start-up CxA performs/oversees functional testing
CxA reviews O&M ManualsCxA oversees staff training
Substantial Completion CxA prepares Draft Final Report CxA prepares Systems Manual
Post Construction CxA performs/oversees deferedtesting
Occupancy CxA delivers Final Report CxA provides Warranty and occupant concerns review
OWNER & DESIGN TEAM DOCUMENTATIONOwners Project Requirements (OPR)► Owner and User requirements► Environmental sustainability goals► Energy efficiency goals► Indoor environmental quality requirements► Equipment and systems expectations► Building occupant & O&M personnel requirements
Basis of Design (BoD)► Primary design assumptions► Standards► Narrative descriptions
Cx DURING DESIGN
Work with design team to define measurable energy and indoor environmental quality goals
Discuss alternatives to traditional design solutions Provide support for unfamiliar technologies Review to verify design meets objectives and technologies
properly implemented Review to verify equipment specified meets goals and
objectives
COMMON DESIGN ISSUES
No design target for energy use Lighting power density not identified No heat recovery Condensing boilers not considered Variable speed pumps and fans
ECM motors not incorporated 20°F rather than 40°F design
temp drop design used Undersized piping and
ductwork
Cx PLAN
Overview of Cx Process List of equipment and systems to be Cx Cx Team and responsibilities Management, Communication and Reporting Overview Cx Process Overview (Outline above) List of deliverables Milestones
Cx MEMBERS & RESPONSIBILITIESCOMMISSIONING AGENT Owner’s rep leading commissioning Reviews and produces most paperwork Directs testing Ensures LEED™ requirements are metOWNER Provide support as required to ensure Cx
proceeds smoothly FM Staff?Consultants Provide documentation as required for review Attend commissioning meetings as required
GENERAL CONTRACTOR► Ensures contractors meet commissioning
requirements
M&E CONTRACTORS► Completes start-up, installation verification lists► Operates equipment for Performance Testing► Produces O&M manuals, Provides owner trainingCONTROLS CONTRACTOR► Operate controls for Performance Testing, produce
O&M materials for controls
Cx MEMBERS & RESPONSIBILITIES
Cx SPECIFICATIONS
Contractor responsibilities Submittal review process Meetings IVC process Start-up process Balancing reviews FPT process O&M manuals requirements Training requirements Warranty review
Cx DURING CONSTRUCTION
Verify equipment installed per drawings and specs, manuf’rs requirements and proper industry practice and standards
Verify equipment is, set-up, adjusted, balanced, controlled and operated to provide expected comfort and energy performance
Provide owner complete systems O&M docs Provide owner’s operating personnel
adequate training to understand, operate and maintain equipment
COMMON INSTALLATION ISSUES
Coils piped backward Maintenance access not
provided Pumps with shaft oriented
improperly Thermostats located adjacent
to heating/cooling diffusers Insulation missing Sensors improperly located
COMMON FUNCTIONAL TESTING ISSUES
Controls functions not matching sequence
VFDs do not modulate Outdoor damper minimum
position Control valve action reversed
TRAINING TOPICS
General purpose of system Use of O&M manuals Operation of systems under all conditions Interaction with other systems Adjustments and optimization for efficiency Health and safety Special maintenance and replacement resources Occupant interaction Controls training
SYSTEMS MANUAL
Final BoD System single line diagrams As-Built sequences, set-points, etc. System operating instructions Maintenance schedule Retesting schedule
Cx AFTER OCCUPANCY
Follow trends on BAS to ensure ongoing operation Completion of deficiencies remaining after
construction Follow-up on warranty issues arising Follow up on occupant concerns during warranty
and first year occupancy Verify that issues are cleaned up by the end of
warranty
FINAL REPORT
OPR Design and shops review summary Cx specifications IVC results FPT results O&M evaluation Value achieved through Cx Outstanding issues
MULTI-FUNTION AHU
DESIGN ISSUES Dehumidifying only
outdoor air reduces size of equipment and increases efficiency of equipment
Using heat recovery to reduce load on cooling coil
Using indirect evaporative cooler to increase HX eff’yhumidity carried outdoors
MULTI-FUNCTION AHU
INSTALLATION ISSUES No radiation shield on sensor by flame No maintenance access to some
sensors Installation of single point sensor
where averaging required Reset button set tight and vibration
causing unit to cut out Overloads not set properly
BOILERS
DESIGN ISSUES No check valves would
required both boilers operate in parallel
Independent controllers would not have been coordinated
Primary only loop with DHW would have required continuous minimum 160F
BOILER
INSTALLATION ISSUES Water treatment eliminated by
aluminum boiler manufacturer. But piping not protected
OA reset not programmed because tech believed it would not save energy
Control sensor located in single boiler supply rather than common header
RETIREMENT RESIDENCE
HVAC SYSTEM
Ground loop coupled distributed heat pumps with supplemental gas-fired heating.
One AHU with heat recovery and HP htg/clg for fresh air distribution to corridors and common areas
One AHU with WLHP htg/clg for Kitchen
Individual HRVs for ventilation and WLHPs for htg/clg in each room
RETIREMENT HOME
DESIGN ISSUES
Heat injection before rather than after ground loop
Moved to eliminate boiler heating ground
HX between building loop and ground loop removed
Reduced capital cost and increased efficiency
RETIREMENT HOME Cont’d
Dedicated DHW heaters simplified boiler loop controls, allowed summer shutdown and allowed primary loop OA reset and condensing
Cascading different temperature loops ensured cold return water temps
40°F temp rise drop reduced pipe and pump sizing
SHOP DRAWING REVIEW FINDINGS1. 3 re-submittals of heat wheel shop drawings required
before a workable defrost strategy provided.2. Shop drawing coil performance based on water while
system will used propylene glycol.3. Coils have greater air-side and water-side pressure
drops than specified.4. Controls sequences were carbon copy of engineer’s
general wording rather than converting to specifics that can be programmed. Heat wheel, heating coil and cooling coils shall be
sequenced to provide energy efficient operation
AIR HANDLER
SERVICES and REPAIR BUILDING
HVAC SYSTEM
Ground Source Heat Pump Radiant floor heating Dedicated outdoor air ventilation with heat recovery Supplemental fan coils for cooling
SERVICE and REPAIR BUILDING
HVAC System
SMALL SERVICES BUILDING
Functional Testing
System relied on heat pump circulator but never programmed to operate when heat pump off
PID loops needed tuning to provide stable operation Radiant floor valve found with wire not connected leaving
valve open and space overheating
SERVICE AND REPAIR BUILDING CASE STUDYFUNCTIONAL TEST Storage room hot, office cool. Found crossed floor loops. Office
t’stat controlling floor heat in storage room. Loops not labelled
Heat pump constantly tripping. Supplier blamed system but did not measure any parameters. Cx measurements showed water flows ok. Heat pump diagnostics finally found faulty TX valve and low refrigerant.
Controls are probably the single most important item in ensuring successful system operation for comfort and energy savings.
CC programmed system heating water temps lower than specified because this works better
Improperly programmed 24 hr moving average outdoor temp caused the system to flip-flop between heating and cooling
REAL PERFORMANCE
What is the energy use of typical buildings?
0
100
200
300
400
500
600
700
800
All Bldgs (ON)
C&I Accom (ON)
Offices (ON)
Offices (CAN)
GoG
AnnualEnergy
ekWh/m2
All data (except GoG) from NRCan Survey (CIBEUS, 2000).
RETIREMENT RESIDENCE AActual Performance
0
50
100
150
200
250
300
Dec '04 (SL) Nov '05 (SL) Nov '05 (CBIP) Jul '06 (Review) Apr '07 to Mar '08
Simulated
Actual
AnnualEnergy
ekWh/m2
Floor Area = 5348 m2
0
50
100
150
200
250
Aug '04 (SL) Feb '06 (CBIP) Aug '06 (Review) Aug '07 to Feb '08
Simulated
Actual
RETIREMENT RESIDENCE BActual Performance
Floor Area = 11702 m2
AnnualEnergy
ekWh/m2
LABORATORY BUILDINGActual Performance
AnnualEnergy
ekWh/m2
0
100
200
300
400
500
Aug '04 (SL) Aug '06 (CBIP) Feb '07 (Review) Dec '07 to Feb '08 Mar to May '08
Simulated
Actual
Floor Area = 9350 m2
COMPARISON
AnnualEnergy
ekWh/m2
Actual energy use compared to typical buildings
0
100
200
300
400
500
600
700
800
All Bldgs (ON)
C&I Accom (ON)
Offices (ON)
Offices (CAN)
GoG VA SSJ KPHQ TRCABuildingA
BuildingB
BuildingC
BuildingD
MMM Group Limited100 Commerce Valley Drive WestThornhill, ON Canada L3T 0A1t: 905.882.1100 | f: 905.882.0055e: [email protected]