ExecutiveSummaryTheLow-SlopeCommercialRoofingIndustryintheNortheastUnitedStatesandtheOzoneTransportCommissionModelRuleforAdhesivesandSealants:AStudyofRisksandOptionsforEffectiveImplementationPreparedfortheEPDMRoofmgAssociationForsubmissiontotheMarylandDepartmentoftheEnvironmentJanuary12,2008Dr.JamesL.Hoff,DBATEGNOSResearch,Inc3575SeminoleDr.609PostWayCarmel,IN46032Tubac,AZ85646Tel317-679-1542www.tegnos.orgUNDERSTANDINGTHEBUiLDINGENVELOPE“EPDM Roofing Association Executive Summary Maryland wishes

to limit emissions

of volatile organic compounds (VOCs) from adhesives, sealants
and primers. While
the EPDM Roofing Association supports

this objective,

we would like

to recommend

a two-season approach that may offer

an effective optimization

of the competing
goals

of VOC reduction

and effective roofing practice. Analysis:

• Currently, high-VOC bonding adhesives dominate

the commercial membrane roofmg market. • The commercial roofing industry

is currently working

on several technologies

that may reduce
the VOC content

of bonding adhesives,

but these technologies

have not yet been tested and demonstrated

on

a large scale, especially

in the Northeast United States. • Although

the CARB model rule

is described

in the preamble

of the OTC Model Rule

to be

a “reasonably available control technology,”

the CARB rule was developed

in

a region

of the United States with climatic
and economic factors that may differ significantly

from the Northeast United States. • Many

of the adhesives developed

by the roofmg industry

to meet the requirements

of the California-based

model rule were also developed

to be effective primarily within
the climatic
and market conditions

that occur

in California;

and some
of these conditions differ significantly

from conditions

and practices

in the Northeast. • The average temperature differentials between

the California

and Maryland during
the late fall, winter,
and early spring,

are very different
with average temperatures

for the Maryland cities declining

and dropping below 40°F. • Alternative technologies

carry cost penalties between

two and four times the cost of current high-VOC bonding adhesives. Although
cost may not be an overriding consideration

in view
of the larger mission

to reduce
the environmental
impact

of VOCs, this cost differential
must
be considered

in terms

of its past effect

in restricting research

and new product development. • Roof membrane bonding adhesives
may also be formulated using low-VOC solvents, including acetone
and water. Because these solvents

do not volatize

at low temperatures,

their operating range

is typically limited

to temperatures consistently

at or above 40°F. • Because

of differences

in application
skills and methods,

any abrupt change made
by the roofing contractor community
could increase

the risk of compromised roofing installations

and roofing-related construction litigation. • Because

low temperature extremes

at the beginning

and the end of the Northeast ozone season may frequently

fall below
the optimal operating range for low-VOC
roof bonding adhesives,

and because

the commercial roofing industry

in Maryland

has yet to implement

an extensive education

and training program

for its 20,000 workers,

it would

be reasonable

to further provide

a transitional period that would temporarily
allow the use of high VOC adhesives during
the critical months

at the beginning

and end of the ozone season. •

It is interesting

to note that

a similar two-season approach

has already been proposed

for the asphalt paving industry

in the state
of Connecticut. Recommendation:

• Use the Proposed Connecticut Asphalt Paving Rule

as

a Model

for Commercial Roofing

in the Northeast which

is a two-season approach. • Provide

a Transitional Period

for Roofmg Contractors

to Adapt

to Low-VOC Adhesives. Year:

250

p
/

I Required Durinp: 2009

July through August 2010

June through September 2011

May through September • Develop

a Reliable

and Effective Industry-Sponsored
Program

to Assure Compliance

with

a Seasonal Approach. For

a copy
of the full report, please contact

the EPDM Roofing Association

at 301-654-5090.TheLow-SlopeCommercialRoofmgIndustryintheNortheastUnitedStatesandtheOzoneTransportCommissionModelRuleforAdhesivesandSealants:AStudyofRisksandOptionsforEffectiveImplementationPreparedfortheEPDMRoofmgAssociationForsubmissiontotheMarylandDepartmentoftheEnvironmentJanuary12,2008Dr.JamesL.Hoff,DBATEGNOSResearch,Inc3575SeminoleDr.609PostWayCarmel,IN46032Tubac,AZ85646Tel317-679-1542www.tegnos.orgrrnUNDERSTANDINGTHEBUILDINGENVELOPE‘VThe Low-Slope Commercial Roofing Industry

in the Northeast United States and the Ozone Transport Commission Model Rule for Adhesives

and Sealants: A Study

of Risks and Options

for Effective Implementation TABLE

OF CONTENTS

Page 1. INTRODUCTION

3 2. STUDY OBJECTIVES

5 3. ANALYSIS

6 A. VOC Reduction

in Roofing Systems: Technology Review B. Climatic Factors: California

v. Northeast

U.S. C. Product Usage Factors: California

v. Northeast

U.S. D. VOC Emissions

and Commercial Roofmg Adhesives 4. OVERALL
RISK ASSESSMENT

14 A. Wind

& Storm Risks B. Training

& Performance

Risks C. Seasonal Work Disruption

and Uncertainty 5. CONCLUSIONS

16 6. RECOMMENDATIONS

18 Copyright
2007 TEGNOS Research,

Inc.

21. INTRODUCTION As part of

a regional effort

to achieve Federally-mandated eight-hour ozone standards

in the Northeast

and Mid-Atlantic regions

of the United States,
the Ozone Transport Commission
(OTC) developed

a Model Rule for Adhesives

and Sealants (OTC Model Rule). The provisions

of this model rule limit emissions

of volatile organic compounds (VOCs) from adhesives, sealants
and primers.

The OTC Model Rule achieves VOC reductions through
two basic mechanisms:

1) sale and manufacture restrictions

that limit the VOC content

of specified adhesives, sealants

and primers sold

in the state, and
2) use restrictions

that apply primarily

to commercial/industrial applications.

The OTC Model Rule was published

by the OTC

in 2007, with the stated goal of adoption

and enforcement

by individual states and local pollution control districts

on or before January 1,2009. The OTC Model Rule

is essentially identical

to

a similar model rule published

by the California

Air Resources Board (CARB)

in 1998.

In the years 1998-2001,

the provisions of the CARB rule were adopted

in regulatory
form by various

air pollution control districts

in the state of California. Although

the CARE model rule

is described

in the preamble

of the OTC Model Rule

to be

a “reasonably available control technology,”

the CARE rule was developed

in

a region

of the United States with climatic
and economic factors that may differ significantly

from the Northeast United States.

In addition, these climatic

and economic factors may have

a significant influence

on the effectiveness

and overall impact

of the OTC Model Rule
on the environment

and economy

of the Northeast. The commercial low-slope roofing industry may provide

an important example

of how

a model rule based

on the climatic

and market demands

of California

may adversely impact such

a rule’s effectiveness

in other areas
of the country. Although

it accounts

for

a relatively small portion

of the larger economy within
the Northeast United States,
the commercial roofing industry provides

a vital service

to assure public safety and support commerce.

By assuring

the weather-tight integrity

of buildings, properly installed

and maintained commercial
roofs protect

the public from damage from storms
and minimize long-term health problems associated
with mold and other problems associated
with leaky roofs. And by developing application technologies

that can be utilized throughout the entire year

in the Northeast United States, commercial roofers enable
the larger commercial construction industry

to operate

on

a year-round
basis. Unfortunately,

many

of the adhesives developed

by the roofing industry

to meet the requirements

of the California-based

model rule were also developed

to be effective primarily within
the climatic

and market conditions

that occur

in California;

and some
of these conditions differ significantly

from conditions

and practices

in the Northeast.

As an example,

the adhesives
used

to secure modern roofing membranes

to the roof surface (“bonding adhesives”)

are generally effective

and can only
be applied when ambient

air temperatures

are
at or above 40°F and rising. While average minimum daily temperatures in California usually exceed

the 40°F minimum,

this temperature

is generally

not available

in the Northeast

for many fall, winter
and spring months.

As

a result,
the conditions

that currently allow the commercial roofing industry

to provide
safe and

3durable roofing systems

for the Northeast

in all seasons

of the year may not be available with the promulgation

of the OTC Model Rule

in its current form. And although

the commercial roofing industry contributes

a relatively small portion

of overall VOC emissions

in the Northeast,

the industry may bear

a disproportionately
negative impact under the OTC model rule. And

in turn, this impact may significantly impede

the roofing industry’s effectiveness

in keeping buildings

dry and allowing commercial construction activity

to proceed

on

a year-round basis. Because

of concerns regarding

the overall impact

of the OTC Model Rule, several organizations representing

the commercial roofing industry have commissioned

this study
of the OTC Model Rule and its impact

on commercial roofing

in the Northeast.

42.STUDYOBJECTIVESA.IdentifytheavailabletechnologiesforreducingVOCsincommercialroofingsystemsandevaluatetheirsuitabilityandeffectivenessforuseintheNortheastUnitedStates.B.IdentifyandquantifythedifferencesbetweenconditionsinthestateofCaliforniaandNortheaststatesthatmayaffecttheoverallutilityandeffectivenessoftheOTCModelRuleasitappliestothecommercialroofingindustry.C.IdentifyandquantifyandpotentiallysignificantadverseeffectsoftheOTCModelRuleandcommercialroofinginregardtocommerceandpublicsafetyinNortheaststates.D.IdentifypossibleoptionsthatmaymaximizetheeffectivenessoftheOTCModelRuletoreduceroofing-relatedVOCemissionsinNortheaststateswhilealsomaintainingtheeffectivenessoftheroofingindustrytoperformitsroleofprotectingthepublicandpromotingcommerce.53. ANALYSIS A. VOC Reduction

in Roofing Systems: Technology Review VOCs

in modern low-slope commercial roofing systems come primarily
from three sources:

1) splicing adhesives
used

to bond the edges

of roofing membranes

to each other, 2) bonding adhesives
used

to bond the surface

of roofing membranes

to roof substrates and walls, and
3) sealants used

to seal edges and terminations

of roofing membranes

to walls and roof projections.

Of the three VOC product categories,

two categories already employ low-VOC
(less than 250 g/l) formulations throughout

the United States and North America.

In the case of splice adhesives, almost

all single-ply roofing seams
are currently mated using either 100% solids tapes
(in the case of EPDM

or rubber roofing materials), heat-welding

(in the case of PVC

/ TPO

or thermoplastic roofing materials),

or hot asphalt

(in the case of traditional asphalt
and modified bitumen roofing materials).

In the case of sealants, low-VOC,
100% solids products

are both widely available

and widely used throughout North America. Given
the widespread

use of low-VOC splicing
and sealing technologies,

the remaining category

of bonding adhesive appears

to be accountable

for the overwhelming majority

of VOCs produced

in commercial roofing. This

is due

to both the current typical high-VOC content

of the adhesives

as well

as the overall quantity

of roof surface area requiring bonding

as compared

to the relatively small areas requiring panel seaming

and edge sealing. The amount

of VOCs generated

by bonding adhesives
may vary with the type of roofing system
and the type of adhesive employed.

In the case of asphalt roofing membranes,

hot asphalt

is the predominant adhesive, either applied with

a mop

to the membrane surface or derived from the membrane using

a roofing torch.

In the case
of single-ply membranes,

the predominant adhesives

are contact adhesives

that are sprayed

or roller- applied

to both the membrane surface
and the roofing substrate. These bonding adhesives are composed

of polymeric resins suspended

in

a variety

of solvents.

The majority

of the solvents

in single-ply bonding adhesives
used today contain VOCs

at rates higher than the 250 g/l standard established

in the OTC Model Rule. Examples

of these solvents include toluene, hexane
and heptane. Because these solvents volatize

at relatively

low temperatures,

they allow
the effective application

of single-ply roofing membranes within a relatively
wide temperature
range— from below freezing

up to 100°F and beyond. Because

of this wide useful temperature
range, bonding adhesives using high VOC solvents

are the preferred product choice

for the commercial roofing contractor. Roof membrane bonding adhesives
may also be formulated
using low-VOC solvents, including acetone
and water. Because these solvents

do not volatize

at low temperatures, their operating range

is typically limited

to temperatures consistently

at or above 40°F.

In addition, because they tend

to vol atize more slowly than high-VOC solvents,
they are much more affected

by ambient conditions,

such

as relative humidity

and solar shading factors.

As an example,

a roofing membrane exposed partially

to the sun and partially

in the shade may “over dry”
on the sunlit surface while
the shaded surface remains

too wet

6forinstallation.Iftheadhesiveisallowedtodrytoolong,theadhesivebondmaybeweakenedandtheoverallwindupliftresistanceoftheroofingsystemmaybecompromised.Andiftheadhesiveistoowetwhenthemembraneisinstalled,theroofwilllikely“blister,’alsocompromisingoveralladhesion.Asaconsequence,theeffectiveuseoftheseadhesives—evenunderoptimaltemperatureconditions—requiressignificantawareness,trainingandexperienceonthepartoftheroofingcrew.Currently,high-VOCbondingadhesivesdominatethecommercialmembraneroofingmarket.ShippingreportsfromEPDMRoofingAssociation(ERA)membersindicatethatover95%ofallsingle-plybondingadhesivessoldintheUnitedStatescontinuetoemployhigh-VOCformulations.Theonlyregionofthecountrywherelow-VOCbondingadhesivescurrentlydominateisthestateofCalifornia,wherelow-VOCbondingadhesiveshavebeenmandatedsincethelateI990s.Thiswouldappeartoindicatethatcustomerpreferencewillbedifficulttochangewithoutamandatedregulation.However,thisalsosuggeststhatlittlelearning,preparationoradaptationtothespecialapplicationrequirementsoflow-VOCadhesiveshasoccurredoutsideofmandatedregions.ThecommercialroofingindustryiscurrentlyworkingonseveraltechnologiesthatmayreducetheVOCcontentofbondingadhesives,butthesetechnologieshavenotyetbeentestedanddemonstratedonalargescale,especiallyintheNortheastUnitedStates.Examplesofthesetechnologiesincludepolyurethanefoams,100%solids,highmolecular-weightsolvents,andthixotropiccompounds.Thesetechnologiesappeartooffervalueinaddressingtheneedsoftheroofingindustry,especiallyinadaptingtotheextremetemperaturerangerequiredforrooftopapplication.However,eachofthesetechnologiesalsocomeswithrisksthathavenotyetbeenfullyevaluated.Examplesoftheserisksinclude1)applicatorfamiliarityandtraining,2)long-termdurabilityandservicelife,and3)healthconcernswithsomeofthechemicalsinvolved.Inaddition,allofthesealternativetechnologiescarrycostpenaltiesbetweentwoandfourtimesthecostofcurrenthigh-VOCbondingadhesives.AlthoughcostmaynotbeanoverridingconsiderationinviewofthelargermissiontoreducetheenvironmentalimpactofVOCs,thiscostdifferentialmustbeconsideredintermsofitspasteffectinrestrictingresearchandnewproductdevelopment.Becauseroofingcontractorsandtheirbuildingownercustomershavebeenveryreluctanttopaythecurrentcostpremiumsrequiredbyalternativetechnologies,roofingmanufacturershavebeenunabletoconductextensivetestingandmarketingoftheseproducts.Givensufficientdevelopmenttime,however,roofingmanufacturersappeartobeconfidentthatasuccessfultransitioncanbemadefromtoday’shigh-VOCbondingadhesivestonewlow-VOCalternativesthatcansuccessfullyaddresscoldtemperatureapplications.B.ClimaticFactors:Californiav.NortheastU.S.AcomparisonofclimatebetweenCaliforniaandMarylandindicatesbothsimilaritiesandcontrasts.Figure1comparesaveragemonthlyminimumandmaximumtemperaturebetweencitiesinsouthernCalifornia(LosAngeles),northernCalifornia(Oakland),coastalMaryland(Baltimore),andinlandMaryland(Hagerstown).7Figure

1: Monthly Average High and Low Temperatures (Source:

The Weather Channel) 90

Las Angeles, California ::..•: :::

: SO

6 :: 30

Ozone Season 20

(Northeast

US) 10 Jan F.b Mar Apr May Jun
Jul Aug Sep Oct Nov 0.0 Oakland, CalifornIa__________ 90 60 40 30

Ozone Season 20

(Northeast

US) 10 Jan F.b Mar Apr May Jun
Jul Aug S.p Oct Nov D.c Baltimore, Maryland 30

1

Ozone Season

3 (Northeast

US) 20 10 Jan F.b Mar Apr May Jun
Jul Aug S.p Oct Nov De Hagerstown,

MD 100 OF..

E

2 Jan F•b Mar Apr May Jun
Jul Aug S.p Oct Nov 0. Av.rag. High

Av.rage
Low Op.ratlng Rang.

of VOC-Compliant SIngi.-Piy Rooflng Gondlng Adh.aiv. under OTC Mod.) Ru). (<250 gm

/ I)

8DuringthesummermonthsofJunethroughAugust,averagehighandlowtemperaturesforLosAngelesandBaltimorearenearlyidentical,whileOaklandandHagerstownareslightlycooler.Duringthelatespringandearlyfall,thetemperaturedifferentialbetweenthetwoCaliforniacitiesandthetwoMarylandcitiesbeginstowiden,asboththeaveragehighandlowtemperaturesintheMarylandcitiesdeclinebelowtheaveragesfortheCaliforniacities.However,evenduringtheearlyfall(September)andlatespring(May),bothhighandlowaveragetemperaturesfortheMarylandcitiesfallwithintheoperatingrangeforcurrentlyavailableVOC-compliantmembranebondingadhesivetechnologiesmentionedpreviously.ItshouldbenotedthattheperiodfromMaythroughSeptember,whenaveragetemperaturesfortheMarylandcitiesfallwithintherangeofcurrentVOCcompliantbondingadhesivetechnology,coincideswiththe“OzoneSeason”fortheNortheastUnitedStatesasdefinedbytheOzoneTransportCommission.Theaveragetemperaturedifferentialsbetweenthetwostatesincreasesfurther,however,duringthelatefall,winter,andearlyspring,withaveragetemperaturesfortheMarylandcitiesdeclininganddroppingbelow40°F.DuringthemonthsfromNovemberthrough-March,averagetemperaturesfortheMarylandcitiesareeitherwellbeloworbarelyattheminimumoperatingtemperaturesrequiredforcurrentVOC-compliantroofingmembraneadhesivetechnology.Itshouldbenoted,howeverthattheperiodfromOctoberthroughApril,whenaveragetemperaturesinWashingtondropbelowtherangeofcurrentVOCcompliantbondingadhesivetechnology,fallsoutsidethe“OzoneSeason”fortheNortheastUnitedStatesasdefinedbytheOzoneTransportCommission.9The challenges

of the winter months

in the Northeast

are even more pronounced

in terms of low temperatures,

as shown

in Figure

2 for the cities

of Baltimore

and Hagerstown: Figure

2: Monthly Record High and Low Temperatures(Source:TheWeatherChannel)10080e40200-2010080€040200-20Baltimore.MDJanF.bMarAprMayJunJulAugS.pOctNov0.0Hagerstown,MDJanF.bMarAprMayJunJulAugSapOctNovD.cR.cordHighR.ccrdLow...Op.r.tlngRang,ofVOC-CompliantSingl.-PiyRoofingBondingAdh.siv.und.rOTCModa4Rul.(250gmII) Even during
the most extreme events recorded,

the high and low temperatures

in the California
cities still fall within
the operating range
for currently available VOC compliant membrane bonding adhesive technologies throughout

the entire year.

In Maryland, however,

the designated “ozone” months

of May and September, which appear

to be hospitable

to low-VOC bonding adhesive

in terms

of average temperatures, may frequently experience

low temperatures

well below
the 40°F minimum

for successful application

of low-VOC bonding adhesives.

rn — — — :::::::.::::::::..::.:::.:.:Ozen•S.aaon-7(North.astUS)-: ——----:-

L 10C.ProductUsageFactors:Californiav.NortheastU.S.1)HistoricalDevelopmentoftheU.S.RoofmgMarket.Priortothedevelopmentofmodemsingle-plyroofingmembranesinthe1970sand1980s,almostallcommercialroofsintheUnitedStateswereconstructedofasphaltmaterials,typicallyinredundantlayersofroofing“felt”embeddedinprogressiveapplicationsofhotasphalt.However,thedominanceoftraditionalasphaltroofingbegantodeclineduringthe1970sduetoanunusualconfluenceofevents.TheArabOilEmbargoforcedrefineriestoderivemoreandmoregallonsofgasolinefromeverybarrelofoil.Asaconsequence,theasphaltremainingatthe“bottomofthebarrel”containedfewerplasticelementsandbecamemorebrittle.Increasingconcernsaboutthehealthhazardsofasbestosexertedasimilareffectonroofingfelts,asasbestoswasreplacedwithweakerorganicmaterials.Theoilembargoalsoincreasedconcernsaboutenergyconservation,drivingupthethicknessofroofinsulation.Asroofinsulationthicknessincreased,theoverlyingasphaltroofmembranebecameisolatedthermallyfromtheremainderofthebuilding.Asaresultofthis“thermalisolation,”theroofingmembranebecamesubjecttoincreasingtemperatureswingsfromsolarheatingduringthedayandfreezingtemperaturesatnight.Frequently,theembrittledasphaltandtheweakenedroofingfeltsfrequentlywereunabletoaccommodatethethermalmovementproducedbythesetemperatureswings.Startinginthe1970ssingle-plyroofingmembranesmadefromrubberandplasticmaterialsbegantosupplanttraditionalflatasphaltroofing.Inplaceofredundantlayersoffelts,thesematerialsprovidedasingle,monolithicwaterproofinglayer.Andinsteadofhotasphalt,single-plymembraneswerefrequentlyattachedtotheroofingsubstratewithcontactadhesives.Duringthe1980s,salesofsingle-plymembranesbegantoaccelerate,drivenbythegrowthofonetypeofmembraneinparticular:EPDM,orrubberroofing.Bytheendofthel98Os,annualsalesofEPDMroofingmembraneshadgrowntooveronebillionsquarefeet,orapproximately1/3oftheentirelow-slopecommercialroofingmarketintheUnitedStates.2)RegionalMarketDifferences.ThestronggrowthofEPDMroofingwasnotuniformthroughouttheUnitedStates,however.InregionswithinfrequentfreezingtemperaturessuchastheWestandSouthwest,asphaltmaterialscontinuedtodominate.However,inregionswithfrequentfreezingtemperaturessuchastheMidwestandNortheast,EPDM’sshareofthecommercialroofingmarketexceedsits33%nationalaverage.Thetrendstartedinthe1980scontinuestobedemonstratedtodayinindustryshipmentstatistics.Figure3comparesthemarketshareofEPDM,asphalt,andothersingle-ply(PVC&TPO)roofingmembranesforthestateofMarylandascomparedtoCaliforniain2006.11Figure

3: Annual Commercial Roofing Membrane Usage (Millions

of Square Feet) (Source: SPRI 2006) 69% 46% CalifornIa 3,000,000

2%

29% In the state
of California

in 2006, EPDM roofing accounted

for only 2% of total lowslope roofing installations,

as compared

to 69% for asphalt membranes. However,

in Maryland

the ratio

is significantly different,
with EPDM membranes accounting

for over 1/3 of all roofing projects. Looking

at the current mix of roofing materials
used

in Maryland

and California,

the data suggests
that product preferences

are influenced

by climate.

In Maryland, where temperature swings
and freeze-thaw
cycle are intense,

the high flexibility

of rubber roofing appears

to be

a significant consumer choice

to avoid premature
roof failure due
to cracking

or splitting. 3) Regional Training

/ Experience Issues. Regardless

of the factors behind

the differences

in product choice between California

and Maryland,

the fact that rubber roofing, which

is

a major product

of choice

in Maryland,

has been rarely used

in California

may bring into question

the OTC assumption

that the experience

of the California market provides

a “reasonably available control technology”

that can be immediately implemented

in either Maryland

or the Northeast. Although Maryland

is much smaller

in terms

of area and population,
every year over
22 million

of EPDM roofs are installed

as compared

to only

3 million square feet
in California. Because

of the paucity

of EPDM installations

in California,

it takes over

7 years
of roofing experience New Jersey EPDM fPVCITPO

Asphaltic

12with EPDM

in California

to equal the experience— and risk- with EPDM installations occurring

in Maryland

in

a single year. Just

as little practical experience relevant

to the Northeast

may have been obtained from California’s mandate

for low-VOC bonding adhesives,
little

if any effort has yet been made

to provide training

for Maryland roofing workers

in regard

to effective application of low-VOC products. According

to

a survey

of Maryland’s largest commercial roofing contractors,

little

or no formal training

on low-VOC adhesives

has yet been undertaken. In addition, shipment records

of members

of the EPDM Roofing Association indicate
that fewer than 1000 gallons

of low-VOC bonding adhesives

are shipped annually

to Maryland— indicating

that Maryland contractors

and their crews have little

or no experience

with low-VOC adhesives

at this time. The lack of contractor training
and experience

with low-VOC bonding adhesives

is particularly worrisome
since the total number

of roofing workers involved

in roofing installation

is relatively high. The consensus

of roofing contractors contacted

and interviewed

for this study indicates

that approximately
20,000 workers may be involved in roofing applications

in Maryland annually.

In addition,

the contractors report high turnover rates that may increase

this number, especially

in terms

of training needs.

134.OVERALLRISKASSESSMENTA.Wind&StormRisksTheriskfactorsassociatedwithcompromisedroofinstallation—especiallyintermsofadhesivesecurement—alsoappeartobehigherintheNortheastthaninCalifornia.Asillustratedinthe50-yeardesignwindspeedmapoftheUnitedStatesshowninFigure4,largeportionsofCalifornia(especiallythemostpopulatedareas)fallwithinthelowestwinddesigncategoryof70milesperhour.Incontrast,manyareasoftheNortheastfallwithinamuchhigherwindspeedof90to100milesperhour,withevenhigherwindspeedconsiderationsalongAtlanticcoastalareas.Figure4:BuildingCodeDesignWindSpeedsintheUnitedStates(Source:UniformBuildingCode)Inadditiontohigherdesignwindspeeds,theconsequencesofwind-relatedroofingfailuresmaybemuchmoresevereintheNortheast,wherealmostallextremewindsareassociatedwiththecyclonicstormsandhurricanesthatmaydropasmuchas12inchesofwaterinasingleday.Asaresult,whatmightbeaminorwindincidentduringahot“Santa-Anna”gustinCaliforniamaybeamajordisastercausingextensivebuildingdamagecompromisingoccupantsafetyduringasignificantwindandraineventinMaryland.B.Training&PerformanceRisksAlthoughroofingaccountsforonlyabout6%ofthetotalcostofabuilding,theNationalRoofingLegalResourceCenterreportsthatroofingproblemsaccountforover25%ofall0Fio.4mcLkwoRiIBuwticCoocUSEDWFINPERMISSION70Milesperhour•80Milesperhour)90Milesperhour•100MilesperhouraiioMilesperhour•120MilesperhourCoLORvTi-nssruCrER14construction-relatedlitigation.Thishighfrequencyoflitigationhasmaderoofingcontractorsespeciallyconservativewhenitcomestotheselectionofroofingmaterialsandmethods.Infact,themarketdatashowingthatroofingcontractorsinMarylandpreferEPDMroofinginover35%ofallapplicationssuggeststhatthecontractorshaveestablishedadefinitepreferencefortheproducttheybelievewillperformthebest(andkeepthemoutofthecourts)giventhespecificclimaticfactorsinMarylandandotherpartsoftheNortheast.Becauseofdifferencesinapplicationskillsandmethods,anyabruptchangemadebytheroofingcontractorcommunitycouldincreasetheriskofcompromisedroofinginstallationsandrooting-relatedconstructionlitigation.IfroofingcontractorsinMarylandandtheNortheastweretodecidetoreturntoagreaterrelianceontraditionalasphaltsystemsinordertominimizetheirrisk,theywouldhavetore-trainaworkforceofapproximately20,000roofingcrewmemberstore-gainthetraditionalskillsassociatedwithapplyingandcontrollinghotasphalt.IftheroofingcontractorsdecidetostaywithEPDMsystemsandimmediatelyembracelow-VOCbondingadhesives,thesame20,000crewmemberswillagainneedextensivetrainingtoassuretheproperapplicationofanadhesivesystemlittle-usedandlittle-understoodintheNortheast.C.SeasonalWorkDisruptionandUncertaintyWiththeexceptionofextremesnowandiceconditions,roofingworkinMarylandandtheNortheastcontinuesthroughouttheyearregardlessoftheseason.Ifroofingcontractorsareforcedtomovetooquicklytolow-VOCbondingadhesivesthatareunsuitableforapplicationattemperaturesclosetoorbelow40°F,itislikelythatroofing—crewswillbeunabletoworkatallduringthelatefall,winterandearlyspring.Inaddition,evenduringthelatespringandearlyfall,unsuitabledailytemperatureconditionsmayoccuratafrequencythatmaymakeitunprofitableforroofingcontractorstoassembleandmaintaincrewsavailableforworkevenondayswhentemperaturesarefavorable.Thissituationmaynotonlyincreaseunemploymentamongroofingcrewmembers,butthedisruptionmightspreadtotheentirecommercialconstructionindustry,aspartiallycompletedbuildingsitemptyandexposedtotheweatheruntiltemperaturesweresuitabletoinstallroofingmaterials.155. CONCLUSIONS The same data

in this study that identify

the risks associated

with
an abrupt switch

to low VOC bonding adhesives

for roofing

in the Northeast
may also identify

the best approach to avoid many

of these financial

and public safety risks.

At the time
of the year when ozone formation

is of particular concern

to the citizens

of the Northeast, especially during the peak ozone months

of July, August
and September, temperature conditions

are generally suitable

for the use of current low-VOC bonding adhesive technology without overly compromising current roofing practice.
And during
the colder seasons

of year when ozone formation

is not

a concern, traditional higher VOC adhesives could still be made available. Accordingly,

a two-season approach
may offer

an effective optimization of the competing
goals
of VOC reduction

and effective roofing practice. It is interesting

to note that

a similar two-season approach

has already been proposed

for the asphalt paving industry

in the state
of Connecticut.

In

a public hearing May

1, 2007,

a draft amendment

for Subsection

(k) of Section 22a-174-20

of the Regulations

of Connecticut Agencies

was reviewed

at

a public hearing. This amendment, proposed

for implementation
January

1, 2009, calls for

a restriction

on high-VOC asphalt products during
the period from May

1 through September

30 of each year, with
no restriction

on these products during
the remainder

of the year. The amendment

also contains specific requirements regarding

the record-keeping necessary

to assure
the effective implementation

of such

a two-season strategy. Specifically,

the draft amendment

for asphalt paving requires
that
all manufacturers,
sellers,
and contractors
using asphalt paving materials

to maintain

and make available records

of test, formulation,

and usage data, and any other information necessary

to determine compliance

with the amendment for

a period

of five years.

In addition,

the proposed amendment includes

a procedure

to be followed

by members

of the paving industry

in the event

an exception

to the amendment

is required

due

to special circumstances,

such

as extreme cold conditions. Although

the two-season proposal

for asphalt paving may serve

as an example

for

a similar approach

for commercial roofing, there are several differences between

the two industries

that may require minor modification

of the proposed asphalt paving rule

to adopt

it to the roofing industry.

The first difference involves

the relative maturity

of low VOC technology

for paving materials

as compared

to roofing materials.

In the same public hearing mentioned previously,

the hearing officer stated that the technology

of low-VOC asphalt was well-developed

and that the industry
was experienced

with application differences: “Emulsified asphalts
(Ed: Low-VOC technology)

have been proven

to perform

at least

as well

as cutback asphalts
(Ed: High-VOC technology)

for all purposes during
the ozone season.
We recognize

that during
the

I 980s there were problems with emulsified asphalts. Since that time there have been improvements

in the technology

and most applicators
have become comfortable

with the differences

in application between cutback
and emulsified asphalt. Additionally, asphalts
that comply with this amendment

have been

in use and demonstrated

to be

166.RECOMMENDATIONSA.UsetheProposedConnecticutAsphaltPavingRuleasaModelforCommercialRoofmgintheNortheast.TheproposedConnecticutasphaltpavingamendment,callingfortheuseoflow-VOCproductsduringtheozoneseasonmonthsofMaythroughSeptember,providesareasonablebasisforregulationofbondingadhesiveswithinthecommercialroofingindustry.Inordertoaligntherequirementsforthecommercialroofingindustrywiththeproposedruleforthepavingindustry,theOTCModelRuleforAdhesivesandSealantsshouldberevisedsothatthe250gilmaximumfor“Single-PlyRoofMembraneInstallationlRepair”isrequiredonlyduringtheozoneseasonmonthsofMaythroughSeptember.B.ProvideaTransitionalPeriodforRoofmgContractorstoAdapttoLow-VOCAdhesives.BecauselowtemperatureextremesatthebeginningandtheendoftheNortheastozoneseasonmayfrequentlyfallbelowtheoptimaloperatingrangeforlow-VOCroofbondingadhesives,andbecausethecommercialroofingindustryinMarylandhasyettoimplementanextensiveeducationandtrainingprogramforits20,000workers,itwouldbereasonabletofurtherprovideatransitionalperiodthatwouldtemporarilyallowtheuseofhigh-VOCadhesivesduringthecriticalmonthsatthebeginningandendoftheozoneseason.Thisapproachwouldallowcommercialroofingcontractorstofirsttraintheircrewsduringtheoptimalmonthsoftheozoneseason,andthenextendthisexperienceintothelessoptimalmonths.Specifically,itisrecommendedthatthe250g/1maximumfor“Single-PlyRoofMembraneInstallation/Repair”bephasedaccordingtothefollowingschedule:Year:250/1RequiredDurin2009JulythroughAugust2010JunethroughSeptember2011MaythroughSeptemberC.DevelopaReliableandEffectiveIndustry-SponsoredProgramtoAssureCompliancewithaSeasonalApproachThemanufacturermembersoftheEPDMRoofingAssociationareresponsiblefortheshipmentofalmostallrubberroofingmembranesandover90%ofallrubberroofingbondingadhesivesintheNortheastUnitedStatesandMaryland.Giventhebroadinvolvementofthemembersofthistradeassociationinthesaleanddeliveryofrubberroofingadhesives,itwouldbereasonabletocalluponthemtoactthroughtheirtradeassociationtoprovideareliableandeffectiveprogramtoassurethathigh-VOCadhesives18are not available

or used during
the Northeast ozone season. Elements

of this program should include: 1. A moratorium

on shipments

of high-VOC bonding adhesives

into Maryland during
the months

of May through September. 2.
A maximum limitation

on shipments

of high-VOC bonding adhesives

into Maryland during
the months

of March
and April

to reduce
the potential

for stockpiling
prior

to the start of the ozone season. This limitation could

be based on historical shipment records along with

a reasonable percentage increase

for market growth.

In the event that

a very large roofing project requires

an unusual quantity

of adhesive during this period,

an exception program could

be established

to assure and verify that the adhesives

are intended

for specific identified projects scheduled

to be completed
prior

to the beginning

of the ozone season. 3.
A reporting program

to verify that all customer stocks

of high-VOC adhesives have been used prior

to the beginning

of the ozone season,

or that any remaining stocks
are safely stored until the end of the ozone season

or returned

to the manufacturer

for disposal

or re-shipment

to areas
of the country where high-VOC adhesives

are permitted during
the summer. 4. A reporting program

to provide

the Maryland
DEP with annual shipment information

and VOC content

of all rubber roofing adhesives shipped
into Maryland. 5. A requirement

that all manufacturers

and marketers

of rubber roofing systems participate

in the industry program

in order

to be eligible

to ship high-VOC adhesives

into Maryland, along with

a requirement

that the industry program

be available

to all manufacturers

and marketers

of rubber roofing systems regardless of membership

in the industry trade association.

0 19TEGNOS Research,

Inc. was founded

in 2007
by Dr. James

L. Hoff

to serve the building industry

by “Advancing Understanding

of the Building Envelope”

To accomplish

this mission, TEGNOS provides professional services

to trade and technical associations within
the building industry,
with
an emphasis

on research, education

and advocacy. Additional information
about TEGNOS

can be found

at http://www.tegnos.org.

Dr. Hoff currently serves

as the Research Director

of the Center

for Environmental Innovation

in Roofing

in Washington,

DC, and

is

a board member

of the RCI Foundation

and the Performance Council

for Constructed Roofing Systems.

20

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