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C.L.I. Group serves the Greater Cleveland area.

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Whole Building Design& Cx Issues

The “holistic” approach to operating,maintaining & commissioning a facility

Opportunity

“Commissioning America” in a decade is an ambitiousgoal, but achievable and consistent with this

country’s aspirations to simultaneously addressenergy and environmental issues while creating jobs

and stimulating sustainable economic activity.

(These benefits can only be realized through integratedapproach to designing and commissioning buildings)

Our Philosophy

• Buildings are made up of numerous components which should createan integrated, efficient and easily maintainable whole. This integrationand the attention paid to achieving it is what makes buildings performas designed.

• We believe that it takes a “multi-disciplined” team to achieve this goal.A complete understanding of how all of the components of a buildingoperate as a whole is critical to achieving a building that works.

• Our team consists of engineers, architects, test & balance personneland indoor air quality, building envelope, roof and other componentspecialists. This allows us to practice strict quality control from thedesign phase to final occupancy on both new and existing buildings.

Integrated & Holistic Approach

Commissioning as Risk Management

• Commissioning is more than “just another pretty energy-savingmeasure.”

• It is a risk-management strategy that should be integral to anysystematic approach to garnering energy savings or emissionsreductions.

- Ensures that a building owners get what they pay for whenconstructing or retrofitting buildings

- Provides insurance for policymakers and program managersthat their initiatives actually meet targets

- Detects and corrects problems that would eventually surface asfar more costly maintenance or safety issues.

Green Building Solutions

• Whether your goal is LEED, Energy Star, Green Globes orsimply having a building which is safe, durable, energy efficientand environmentally responsible, we can help. Our staffincludes:

– L.E.E.D. Accredited Professionals (NC & EB)

– Energy Star Partners

– Certified TAB Professionals

– Board Certified Indoor Air Quality Professionals

– Building Enclosure Specialists

– Engineering & Architectural Support

What Is LEED-EB

• LEED for Existing Buildings maximizes operational efficiencywhile minimizing environmental impacts. It provides arecognized, performance-based benchmark for building ownersand operators to measure operations, improvements andmaintenance on a consistent scale. LEED for Existing Buildingsis a road map for delivering economically profitable,environmentally responsible, healthy, productive places to liveand work.

• Our specialty is measuring and documenting buildingperformance. Our consultants are LEED AP’s with experience inLEED-NC and LEED-EB

Why Commission?Is There a Need?

Building problems (a.k.a. “deficiencies”) are pervasive• Design flaws; Construction defects; Malfunctioning equipment;

Deferred maintenance• Don’t shoot the messenger: problems a combined result of

fragmentation/specialization of trades, “value” engineering,,increasingly complex building design and operationrequirements, lack of clear design-intent documentation andperformance targets, etc.

• Not attending to problems can cause:– Discomfort --> Eroded productivity, absenteeism– Indoor air quality problems– Premature equipment failure– Litigation– Excessive energy and construction costs

Typical Approach to LEED and BuildingCx

• Most A/E firms approach LEED program and Cx froman office based perspective

• Design, Submittal, O&M Review, electronicsubmission of info to USGBC

• All of this is necessary and a valuable function.

• Typically done very efficiently by A/E groups.

Typical Void

• A/E groups typically leave field services to othergroups – Installing contractors, TAB group, ATCgroup, CxA.

• Lack of field experience with installed systems andmost importantly, interaction of building envelope andmechanical systems.

• Hidden problems typically STAY hidden until yearsdown the road.

Hidden Problems

• Long term problems that arise from seemingly smallitems that go undetected for many years – envelopeair leakage adding unnecessary and unplanned loadsto HVAC systems, leading to condensation problems,and eventually mold.

• May occur in buildings that have had LEEDcertification

TAB Problems

• Many TAB reports that arefalse – conflict of interest forTAB specialist to work formechanical contractor

• TAB reports that areaccurate, but buildingenvelope has beenoverlooked.

Potential Problems/Unresolved Issues

• Control systems don’t realize their full potential oreven design intent.

• Building Degradation & HVAC Systems prematurefailure and underperformance.

• Nuisance repairs in year 1 warranty period thattypically address symptom and not cause.

• Chronic, long term enclosure degradation, moistureproblems, litigation, increased maintenance costs.

Save a Little Now, Pay A lot Later

A recent study of anelementary school showedthat if $8,140 had beenspent over 22 years onpreventive maintenance,$1.5 million in repairs couldhave been avoided.

-Minnesota Dept. ofEducation

Oversights Cost $$

• The cost of oversights duringand after construction can addsignificant costs to the operation& maintenance of the building.

• This image shows poor thermalboundary (open to conditionedspace) A 2 mph draft wasmeasured in attic coming fromconditioned space. This adds toenergy inefficiency and alsocreates building degradationand IAQ issues.

HVAC & The Building Envelope

• Fundamental understanding of each of thesesystems is critical

• Knowledge of how they should, can, and do interactwith each other.

• Knowledge of how to test their performance,individually and interactively.

HVAC Systems

• Structural – system mounting, orientation

• Ducting –airflow

• Piping – water, fuel flow

• Refrigeration knowledge, compressors

• Venting, combustion, AFUE

• Controls & Automation

• Electrical power flow & requirements

• Performance Testing Knowledge

Skill Sets

• Mechanical systems are wide ranging in terms oftypes and can be very complex.

• Designers and contractors typically have areas ofspecific expertise.

• Many projects do not have their project requirementsmatched with designers and /or contractors who havespecific expertise in those skill sets.

• This makes field performance testing a good valuefor owner as it identifies inadequacies early.

HVAC Underperformance

• Various national studies by EPA, DOE, ASHRAE, NCI, BPI,LBNL, and USGBC show staggering statistics on buildingperformance.

• Residential and Light Commercial HVAC systems perform within10% of their design intent in less than 1% of American buildings(when including impact of building envelope).

• Many operate at below 50% of design intent.

• Many installations have not considered indoor air quality.

You Can’t See Air

• Airflow problems in buildings are the single largestcontributor to HVAC system underperformance.

• Often times, even in Cx’d buildings, HVAC systemsdo not achieve their potential because the buildingenvelope deficiencies go undetected.

• Airflows must FIRST be identified. Airflows cannot besuccessfully controlled until they have beensuccessfully identified. This is a common failure inTAB reports.

Commissioning Scope: ExistingBuildings

• Develop or update design intent documentation

• Plan

• Utility analysis, benchmarking

• Trend analysis

• Building modeling

• Findings

• Estimate benefits from interventions

• Update system documentation (e.g. control sequences)

• O&M improvements

• Capital improvements (grey zone)

• Monitor fixes

• Measure impacts

• Systems manual/re-commissioning manual

Cx Costs

Existing Buildings• Cost: $0.27/ft2 • Median NEBs: $0.18/ft2• Deficiencies: 11 per building• Energy Savings: 15%• Payback: 8.5 monthsNew Construction

• Cost: $1.00/ft2 • Median NEBs: $1.24/ft2• Deficiencies: 28 per building• Payback: 4.8 years• Cost-effective over range of energy intensities, bldg types, sizes, locations• Most successful: energy-intensive buildings• Cost-effective outcomes harder in small buildings• Energy savings rise with more thorough commissioning

– Source: Lawrence Berkeley National Laboratory

Commissioning Provides ProperDiagnosis

Avoid the “Quick Fix” Fixingthe symptoms of a building orsystem problem withoutdetermining and addressing theroot causes may providedramatic and immediatesavings, but these savings arenot likely to persist, and thesymptoms may reappear

Benefits of Total Commissioning

• Design intent met &documented

• Lower overall operating& maintenance costs

• Reduced liability

• Increased productivity

• Entities are fullyaccountable for qualityof their work

• Meet owners projectrequirements throughtesting & verification

New Construction

• Don’t Assume!!

• This design allowed roof waterto runoff at wall. The lower roofwas designed to abut parapetfrom larger roof. No kick-outflashing was used to directwater away from parapet.

• Result – damaged parapetmembrane, interior damage,mold, litigation potential.

• This could have easily beenavoided.

Poor Design

• Staining in interstitial spaceshows stains from moisturerunning down sheathing andsteel stud framing.

• This exterior wall consisted ofbrick exterior, 7/8” airspace, ½”gypsum sheathing, steel studframing with paper facedfiberglass batts and ½ interiorgypsum wallboard.

POOR DESIGN!!!

Poor Design

• Enclosure design allowed forexcessive air leakage, poorthermal performance, no dryingcapacity.

• Result – condensation damage,structural degradation, mold,indoor air quality problems.

• A plan review found inadequatecapacity of this wall system todry properly.

• This building showed everythingbuilding science has foundcauses problems.

Is There Help for Bad Design?YES…Good Field Oversight

Envelope Commissioning Pays for Itself

A recent study (June 2005) by the US Department of

Commerce and US Department of Energy showed

the energy impact of improving envelope airtightness

in U.S. commercial buildings.

It predicted potential annual and cooling energy cost

savings ranging between 3% to 36% with the higher

savings in the heating dominated climates with

potential gas savings of greater than 40% and

electrical savings of grater than 25%.

Humidity Control

Architect and Owner shouldrecognize that the foundation ofhumidity control is a tightbuilding. Without thatfoundation, humidity control willbe very difficult and costly toachieve, no matter how well-designed the HVAC systemmight be.

Humidity Control Design Guide for Commercial and Institutional Buildings. Harriman, Brundrett, and Kittler. American Society ofHeating, Refrigerating, and Air Conditioning Engineers. ISBN 1-883413-98-2.

The Missing Link?

The HVAC designer has a pivotal role in avoiding infiltration ofunconditioned air through the building envelope. Avoiding suchleakage is essential to preventing moisture damage to thebuilding, and essential to maintaining control of humidity inoccupied spaces

Humidity Control Design Guide for Commercial and Institutional Buildings. Harriman, Brundrett, and Kittler. American Society of Heating,Refrigerating, and Air Conditioning Engineers. ISBN 1-883413-98-2.

What Is IAQ?

• Introduction and distribution of adequate ventilation air

• Control of airborne contaminants

• Maintenance of acceptable temperature and relative humidity

For IAQ Problems, Four Factors Are Needed…

• A source of contaminants

• A person(s) affected by this source

• A pathway for the transport of the contaminant(s)

• A driving source (e.g. air movement) to transport the contaminant from source tohost

The HVAC System Plays a Critical Role in Three of The Four Requirements

How Does IAQ Affect You?

Failure to respond promptly and effectively to IAQ problems can haveconsequences such as:

• increasing health problems such as cough, eye irritation, headache,and allergic reactions, and, in some rare cases, resulting in life-threatening conditions (e.g., Legionnaire’s disease, carbon monoxidepoisoning)

• reducing productivity due to discomfort or increased absenteeism• accelerating deterioration of furnishings and equipment• straining relations between landlords and tenants, employers and

employees• creating negative publicity that could put rental properties at a

competitive disadvantage• opening potential liability problems (Note: Insurance policies tend to

exclude pollution-related claims)

Energy v IAQ…Are Both Possible?

One Change; Affects Many Systems

Indoor air quality in a largebuilding is the product ofmultiple influences, andattempts to bring problemsunder control do not alwaysproduce the expected result.

De-Pressurization Problems

HVAC Design IS AFFECTED byEnvelope Leakage

Cummings, J. B. C. B. Withers,C.B, N. Moyer, P. Fairey, B. McKendry.1996. “Uncontrolled air flow in non-residential buildings.” Final Report of FSEC, FSEC-CR-878-96. Florida Solar Energy Center, Cocoa, Fla.

Measured leakage rates in 70 commercial buildings (Cummings et al.1996)

BE PROACTIVE!!!

Modeling Is Important in Design Phase

Getting The Performance You Pay For

Poor Design

• Roof draining directly into caststone façade.

• Added kick-out flashing to directwater away from the cast stonefacing.

• This is one of the problemswhen excessive roof lines areused in design.

• Pay attention to the smalldetails!!

Poor Design

• Protrusions and gaps. This isnot good when it comes tokeeping moisture out of yourbuilding.

• Water loves to enter buildingsfrom ledges where it can sit untilit gains access.

• The next slide shows the resultof such building practices.

Poor Design

• Infrared thermography used tolocate leakage before openingwall.

• The O.S.B. sheathing wasfound to be saturated, moldcovered and structurallydamaged as a result of waterpenetrating from protrusion atwindow trim.

• Costly design.

Poor Design Results

Understanding The Problems

• Why Buildings Leak

– Changes-in-plane

– Changes in materials

– Poor design

– Good workmanship based on poor design

– Poor workmanship based on good design

– Time weighted demise of critical components in the presence ofminimal maintenance

– Inappropriate material selection

– Value engineering (This is becoming all too common in ClevelandMarket)

Avoid Waste (Save Our Trees)

• Wasted dollars on wastedmaterials

• Thermal bridging issues(condensation)

• Convective heat losses

• Reduced whole wall R values

• This particular job was framedin this manner throughout

• This IS NOT GREEN Buildingtechnique!!!!

Understand The Problems

• Profit over Performance is theprecedent.

• Poorly trained technicians

• Poor oversight on the jobsite

• More difficult designs, lessqualified installers = poorperforming buildings

• Using the right materials andtrained installers could alleviatemany building problems

Roof Insulation

Corrugated Acoustical Roof Decking

Batts Insulation

Concrete Block Wall Air Pathways

Moisture, Moisture, Moisture

About 50% of total flow,in this measured test byFlorida Solar Energy Center

Leaky Ducts in Unconditioned Space

Does Your Building Suck?

Air Leakage Is a Priority

• Many designers and inspectorspay more attention to vapordiffusion than to air leakage.

• Diffusion of moisture is smallcompared to the amount ofmoisture carried by air leakage.

• Air leakage is one of thecostliest deficiencies inbuildings.

• Results of excessive air leakageare lost energy, buildingdegradation, mold and other iaqissues.

Cx Trouble Spots During Construction

Thermal Bridging Concerns AddressedDuring Envelope Cx

Moisture Management

• “Moisture Damage Contributes to 90% of All Building andBuilding Material Failures” (ASHRAE)

• “Moisture Leading Cause of Building Problems Costing MoreThan $9 Billion Annually in U.S.” (ASTM)

• “Moisture Will Replace Asbestos as the Most FrequentlyMentioned Topic in Building Litigation” (C. Gaal, NJInvestigation Commission Counsel)

– Source: Oak Ridge National Laboratory (U.S.DOE)

Conception through Occupancy

• Moisture issues must be considered from the buildingconception stage

• This consideration must continue through design, constructionand O & M phases

• Model building conditions and construction at design phase tospot potential problem areas

• All flashings, laps, drainage planes, slopes, drip edges must beclearly detailed and dimensioned in drawings

• Project oversight is critical during the installation of these criticaldetails (third party is best)

Don’t Rely on Prescriptive Methods

• Without third party verification of the performance of the buildingenclosure there will likely be problems later on

• Don’t assume that items complying with the code will properlyfunction in the field

• Always assume that mistakes will be made during installations(this is the reason for third party verification)

• Finding problems during commissioning is much more costeffective that finding them after building is completed and muchcheaper to correct

• Pay special attention to the air barrier (this can reduce manymoisture and energy related concerns)

Looks Good, Performs Bad

Looks Good, Performs Bad

The Outdoor Connection

The Outdoor Connection

Hardiplank Siding Issues

Hardiplank Issues

HEALTHcare Facilities?

• The following photo’s were all taken during projects we haveperformed in healthcare facilities.

Condensation Potential?

Frozen Refrigerant Lines in Ceiling

No Insulation = Condensation = Mold

Poor Maintenance = Poor Indoor AirQuality (PTAK Unit in Nursing Home)

Poor Design of Refrigerator in HealthcareFacility = Mold/Water Damage

Condensation Resulting From LeakyEnvelope; Un-insulated Plumbing

Façade Failure = CostlyWater/Environmental Problems

The Price of Procrastination

Early Signs of Water PenetrationThrough Enclosure

Ensuing Damage From UnaddressedRoof Leak

Outdoors WRT Indoors (VinylWallpaper)

Church (Classrooms & Nursery)

Moisture damage Due To PoorEnclosure Design

Significant Damage Visible; MoreDamage Hidden in Interstitial Space

More Cost Saving Results from BuildingManagement

We Covered Those Pesty Holes (Weeps)in The Wall

Value Engineering…Lay-off Supervision

Condensation Potential?

Condensation Potential?

Condensation (Diffusion or AirLeakage?)

All That Moisture (Air Movement =Moisture) Requires “Holistic” Approach

Stack Effect

Inattention to Pressure Causes MajorProblems.

Envelope/HVAC Pressure Connection

Measure, Don’t Guess

Measure, Don’t Guess

TVOC Chart

Log All Conditions for HolisticEvaluation

Modeling

Tying It All Together

• BAS Systems today can domuch more than controllingHVAC systems

• Often plagued by problemswhich lead to under utilizationand under performance

• Control issues lead the list ofsystems found deficient duringcommissioning

• A BAS can makecommissioning more precise,can also aid in LEED issues

FACP Systems

• Fire Alarm Controls mayeither be tied to BAS oroperate independently

• Additional layer of controlswhich require commissioning

• Linked to HVAC systemoperation, damper control,elevator recall, etc.

• Problems here can also leadto problems elsewhere

Daylighting & Controls

• Lighting controlcommissioning iscritical to energysavings

• Lighting controlfailures are oftenrelated to lack ofproper commissioning

• May or may not betied to BAS

Motor Alignment

• Poor energyperformance

• Premature wear

• Poor life-cycleperformance

• Excessivemaintenance costs

Why Are Buildings Failing?

• There are no easy answers to that question. Our experience indicatesthat some of the more important reasons include:

– More difficult systems, less qualified installers

– Poor understanding of holistic building functions

– Single System approaches to energy, moisture problems, comfort,etc.

– Poor understanding of building automation & controls

– Lack of Whole Building Commissioning Agents

– Limited building science and enclosure specialists

– First Cost mentality of many building owners

– Not fully grasping potential problems, costs and liabilities

Thank You!!

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