David Odom, Florida Engineering Society Presentation9/24/08

8/14/2019 David Odom, Florida Engineering Society Presentation9/24/08

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The High Risk of Green Buildings

Liberty Building Forensics GroupMay 2008

The Hidden Risks of Green Buildings

in Hot, Humid Climates:WhichProblems are Likely & How to Avoid Them

Florida Engineering Society

Speakers:

Copyright Liberty Building Forensics Group Duplication by Permission Only 1

David Odom & George DuBose--Liberty Building Forensics Group

Robert ConnerSuncoast Insurance Associates

Maura K. Anderson, Esq.--Smith, Currie & Hancock LLP

idea:

Sue it to death.


Quote from July 14, 2008 ENR magazine


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Presentation Overview

The great irony of building green is that the very concepts thatare intended to enhance a building's performance over itslifetime are many of the same things that also make it highly

years of operation.

Improved energy conservation, increased thermal insulation,and the use of innovative products are some of the thingsthat make buildings green and sustainable. Coincidentally,they are also some of the things that make buildingssusceptible to future failure.


While green buildings have many positive benefits there is also

strong evidence to suggest a direct correlation between newproducts, innovative design, and building failures. Simplyputdeparting from the tried and true often meansincreasing the risk of building failure, and this riskdramatically increases in demanding climates.

Premises of the Presentation Building green is a noble goal, but it can be a riskyendeavor in hot, humid climates

Risks Some are obvious but most are obscure.

Risks include:--Legal & contractual risks

--Insurance risks

--Project risks

--Technical risks

Potential building problems can range from acute &catastrophic to chronic performance failures

Our observation: Good ractices in such ke areas as


IAQ, humidity control, waterproofing & hot/humid climatedesign criteria have not being well integrated into greendesign practices--including many LEED credits.

The answer is to build low risk, regionally correct, greenbuildings


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LEED

Leadershi in Ener & Environmental Desi n

US Green Building Council(USGBC)


What isgreen

building?Design andconstruction

practices thatmeet specified

standards,SitePlanning

resolvingmuch of the

negativeimpact of

buildings on

theiroccupants and

on the

Test

.

LEED is the

current Gold

Standard byUSGBC


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Definitions

Green BuildingDesign, develop, construct &

non-renewable resources.

Sustainability-Includes green issues, but also isinterested in economic issues (financialpayback)


-measurable and verifiable improved outcomes(such as 35% improved energy performance)

LEED-NC Point DistributionIndoor

Envi ronmenta l

Water

Ef f iciency

8%Energy &

Mater ia ls &

Resources

20 %

Susta inable

Si tes

22 %

Qual i t y

23 %


m os p er e27 %


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Leadership in Energy& Environmental Design

LEED

69 Potential Credits (Points)

CertifiedCertified

2 6 3 3 3 9 5 2 6 9


verver

PlatinumPlatinum

GoldGold



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Additional Construction Costs for

LEED-certified buildings

Conventional Building Cost (100%)Average for offices and schools, based on 40 buildings

Additional Cost

(2 buildings)

GOLD (9 buildings)

.

2.2%


SILVER(21 buildings)

CERTIFIED (8 buildings)

1.9%

.66%

Green Building Risks

Legal risks

Insurance risks

Project risks

Technical risks



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Project Risks for Green

Buildings Schedule overruns due to delivery problems with newproducts or the construction impacts of greenrequirements

Cost impacts of sole source products

High expectations of a green building

Not clearly defining what is meant by green

Contractors, subcontractors, and designers who areunfamiliar with green products and innovative approaches


Specifying green products that have minimal in-fieldtesting and poor warranties

Problems that are not covered by insuranceE&O or GCL

Green Buildings

VersusLow Risk, Regionally Correct Buildings

Green Buildings Low Risk Buildings

1. More outside air (> ASHRAE by 30%+) 1. Minimum outside air (not exceed ASHRAE)

2. Stresses innovative materials 2. Stresses time-tested, proven materials

3. Renewable/carbohydrate based matls 3. Hydrocarbon based materials

4. Emphases energy conservation 4. Emphases dehumidification

5. Stresses VOC reduction 5. Minimal VOC concern (only on matl selection)

-Increased exhaust (>5 Pa) -Very tight control of exhaust

-Buildin flush out -Re ects buildin flush out


-Low VOC material selection -Agrees with low VOC materials

6. Stresses extra thermal insulation 6. Stresses drying potential of walls & ceilings

7. Does not address rainwater intrusion 7. Stresses rainwater intrusion avoidance


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Course Agenda

Morning Overview of Green Buildings & Risks-David Odom Specific Technical Higher Risk Green Building Concepts-

George DuBose Problem Prevention Approaches-David Odom

Lunch

Afternoon


Legal Risks of New Design Concepts-Maura Anderson Insurance Issues for Green BuildingsBob Conner

Contract Risks, Contract Forms & Risk Reduction LanguageMaura Anderson Final Tips for Successful Green Buildings-Everyone


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Preventing Green BuildingFailuresSpecific Techniques

to Implement

Summary of the Risks

How to Prevent Problems

What Green BuildingsSh ld L k Lik i th

Copyright Liberty Building Forensics Group Duplication by Permission Only

Should Look Like in the

Southeast

Summary of the Risks in GreenBuildings in the Southeast

Increased OSA ventilation-Is counter to energy conservation-Substantially increases the chance of uncontrolled air flows (pressure imbalances)-Solves problems related to odors increased CO2 and off-gassingSolves problems related to odors, increased CO2, and off gassing-Increases problems related to humidity control

Use of new & untested materials-Warranties that are worthless or misleading-Product data sheets that dont address the major failure points (absorption of water)-Products that are less than 5 years old but will be used buildings that are intended to last 100+

years

Enhanced ceiling & wall insulation-Lower drying potential for wall & ceiling cavities-New products that will act in unknown ways (air, vapor, thermal, and water barr iers)

LEED-Driven, Construction-Phase Activities in Hot, Humid Climates


LEED Driven, Construction Phase Activities in Hot, Humid Climates-Building flush-out during construction

Emphasis on Energy Verification & Under-Emphasis on MoistureVerification

-EA Credit 5: Measurement & Verification. Intent: Provide for the ongoing accountability ofbuilding energy consumption over time.


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Green BuildingsVersus

Low Risk, Regionally Correct Buildings

Green Buildings Low Risk Buildings

1. More outside air (> ASHRAE by 30%+) 1. Minimum outside air (not exceeding ASHRAE)

2. Stresses innovative materials 2. Stresses time-tested, proven materials

3. Renewable/carbohydrate based matls 3. Hydrocarbon based materials

4. Emphases energy conservation 4. Emphases dehumidification

5. Stresses VOC reduction 5. Minimal VOC concern (only on matl selection)

-Increased exhaust (>5 Pa) -Very tight control of exhaust

-Buildin flush out -Re ects buildin flush out


-Low VOC material selection -Agrees with low VOC materials

6. Stresses extra thermal insulation 6. Stresses drying potential of walls & ceilings

7. Does not address rainwater intrusion 7. Stresses rainwater intrusion avoidance

1991 - Omni Hotel

Charleston, SC

Massive Moisture Problems

Occurred ImmediatelyAfter

Opening

The building was de-bricked

and the waterproofing was

repaired, costing >$10M


T e next summer (afterrepairs) the problem re-

occurred.


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Predicting Building Failures in the

Schematic Design Phase


Predicting Future Building

Failures During Early Design



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Elements of a ComprehensivePeer Review Plan

Decreasing Options for SolutionsDecreasing Options for Solutions

Cost ofAction/

SolutionfInfluence

100%

HVACReview

EnvelopeReviews

VEInput Contractor

Submittals

T&B Input PostConstructionPerformance


Design Construction Occupancy

Levelo

0.0%

Source: Adapted from Quality in the Constructed Project, American Society of Civil Engineers, 1988.

Verification

Predicting Wall System

Performance--CondensationPotential

Perms - 5 37.5 34.3 1.6 0.7 2.5 2.5

terior

1. Location of theprimary vaporretarder

2. Location of thefirst plane ofcondensation80 F

95 F

Airfilm

1/2GWB

Paint

Plywood-E

Clapboard

Airfilm

31/2Air

space

3/4Poly-

styrene

95 F

80 F


75 F

Primary VaporRetarder

Dew Point

75 F50% RH

95 F70% RH


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Comparing Wall MoisturePerformance With +2 Pa & -2

Pa Pressures(FL Solar Energy Center Photo)


Materials & ResourcesWall Modeling

PROJECT WallADL-2(WallsCandR)

SummerCondition

REFERENCE: ASHRAE,1989 FUNDAMENTALS,CHAPTER 22 = Input Fi el ds = Calculat ed Fi elds

T HI CK NE SS R - VA LU E V ap o r Re s is t an c e

ASHRAEWALL DEWPONT ANALYS S

WALL DESCRPTION

HHVKaliaTower-ADLChanges

Honolulu,HI

T HI CK NE SS R - VA LU E V ap o r Re s is t an c e

( IN CH ES ) ( F- SF -H /B TU ) ( RE P)

0.000 0.68 0.000

0.625 0.56 0.040

6.000 0.85 0.000

0.625 0.56 0.040

0.000 0.68 0.000

TOTALS: 3.33 0.080

U-VALUE(1/R): 0.30

OUTDOORCONDITIONS: 80.0 FDry Bulb 82% RH

Dewpoint Temperature: 74.0 F 16.0 Elev Ft MSL

Vapor Pressure 0.8468 IN.Hg

INDOORCONDITIONS: 72.0 FDry Bulb 50% RH

Dewpoint Temperat ure: 52. 4F

AIRSPACE

GYPSUMWALLBOARD

INTERIORAIRFILM

WALLSYSTEMCOMPONENT

DESGN CONDTIONS

INTERIORAIRFILM

GYPSUMWALLBOARD

Copyright Liberty Building Forensics Group Duplication by Permission Only 10Temperature Profile

Vapor Pressure: 0.3960 IN.Hg

::

REFERENCE:ASHRAE,1993FUNDAMENTALS,PAGE20.8&20.14

T h ic k ne s s P l an e R -V al u e S u rf a ce T em p S at . V ap o r Pr e ss u re V ap o r Re s is t an c e V ap or P r es s ur e D ew po i nt T e mp R el a ti v e Hu mi d it y

(I nc hes ) Loc at io n (F -SF- H/B TU) ( F) ( in. Hg) ( Rep) Pr of il e ( F) ( %)

OUTDOOR 80.0 0.8468 82.0%

INTERIORAIRFILM 0.000 0.000 0.680 78.4 0.9792 0.000 0.8468 74.0 86.5%

GYPSUMWALLBOARD 0.625 0.625 0.560 77.0 0.9365 0.040 0.6214 64.9 66.4%

AIRSPACE 6.000 6.625 0.850 75.0 0.8750 0.000 0.6214 64.9 71.0%

GYPSUMWALLBOARD 0.625 7.250 0.560 73.6 0.8366 0.040 0.3960 52.4 47.3%

INTERIORAIRFILM 0.000 7.250 0.680 72.0 0.7916 0.000 0.3960 52.4 50.0%

0 0.000 7.250 0.000 72.0 0.7916 0.000 0.3960 52.4 50.0%

0 0.000 7.250 0.000 72.0 0.7916 0.000 0.3960 52.4 50.0%

0 0.000 7.250 0.000 72.0 0.7916 0.000 0.3960 52.4 50.0%

INDOOR 72.0 0.3960 50.0%

VAPORPRESSUREPROFLE

Wall Component


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Use of Innovative & Energy SavingProducts Can Have Unintended

Consequences


Materials & Resources



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VIDEO


Successful Green Buildings in the

Southeast:

Minimizing uncontrolled air flows will be a requirement to controlmoisture and energy. Requirements will be pressure mapping ofu ngs a er cons ruc on an m n m z ng uc wor ea age.

Plenum air supply and return systems will not be used.

Air tightness of building enclosures will be come a requirement andthere will be standards promoted by ASHRAE and others. Dedicated airbarriers MUST be designed into the wall assemblies. Traditionalproducts such as commercial house-wraps and15# paper may becomeextinct in green buildings---too many penetrations & are usually


incorrectly installed

The use of barriers with multiple functions and improvedperformance will be required. For example: use fluid appliedwaterproofing/air barrier materials. They are air barriers, WRB, and canbe vapor retarders (if needed)


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Successful Green Buildings in theSoutheast:

Enhanced water testing of the building envelope; especially windows

& doors prior to installing the insulation

Expandable foam insulation systems may become more common inwalls and ceilin s since the are air barrier va or retarder some

materials) and a high performance thermal barrier. Caution will berequired to avoid moisture problems with foam insulation!

Improving the ventilation effectiveness is more appropriate for hot,humid climates than adding more ventilation. This means designing

better air distribution and verifying it! CO2 monitors will likely becomecommon, but with minimum levels to maintain building pressurization.


u ng per ormance w e ex ens ve y mon ore or mo s ure nojust energy) for at least 1 year

A Southeast Modelof building commissioning is required that willincorporate enhanced design reviews, more involvement by the CA

during construction for waterproofing, and a much enhanced warrantyperiod verification that includes moisture/humidity concerns.

Conclusions1. Building Commissioning (QA) must incorporate:-Enhanced technical peer reviews: HVAC + Envelope + Green Products-Through evaluation of new, innovative materials-Development of a green building design checklist-Water testing of the envelope is more important during construction-Buildin verificationmust include moisturemonitorin not ust ener monitorin ,

2. Perform multiple technical peer reviews during design focusing on:--Predicting interaction of the various building systems--Predicting the buildings post-construction performance--Analyzing the envelope performance--Design team must incorporate the best practices in the fields of waterproofing, humidity

control, and building envelope performance.

3. Design & contractors must place hot/humid climate criteria aheadof LEED credits

4. Closely analyze new products touted as green or innovative,


espec a y pro uc s use n e an u ng enve opesystems. Carefully review warranties, disclaimers, length of in-service testing, and data sheets.

In short, successful design & construction teams in the southeastwill develop a different green building model than USGBC

currently suggests.

David Odom, Florida Engineering Society Presentation9/24/08

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