Q2'20EarningsCallAugust4,2020

Disclosure: Forward-Looking Statements

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Thispresentationcontains,andtheofficersanddirectorsoftheCompanymayfromtimetotimemake,statementsthatareconsideredforward-lookingstatementswithinthemeaningoftheSecuritiesActof1933andtheSecuritiesExchangeActof1934.Theseforward-lookingstatementsaresubjecttoanumberofrisksanduncertainties,manyofwhicharebeyondourcontrol,whichmayincludestatementsabout:thescopeanddurationoftheCOVID-19pandemicanditscontinuingimpactonnationalandglobaleconomicconditions;andourbusinessstrategy;financialstrategy;andplans,objectives,expectations,forecasts,outlookandintentions.Allofthesetypesofstatements,otherthanstatementsofhistoricalfactincludedinthispresentation,areforward-lookingstatements.Insomecases,forward-lookingstatementscanbeidentifiedbyterminologysuchas“may,”“will,” “could,” “should,” “expect,” “plan,” “project,” “intend,” “anticipate,” “believe,” “estimate,” “predict,” “potential,” “pursue,” “target,”“continue,”thenegativeofsuchtermsorothercomparableterminology.Theforward-lookingstatementscontainedinthispresentationarelargelybasedonourexpectations,whichreflectestimatesandassumptionsmadebyourmanagement.Theseestimatesandassumptionsreflectourbestjudgmentbasedoncurrentlyknownmarketconditionsandotherfactors.Althoughwebelievesuchestimatesandassumptionstobereasonable,theyareinherentlyuncertainandinvolveanumberofrisksanduncertaintiesthatarebeyondourcontrol.Inaddition,management’sassumptionsabout future events may prove to be inaccurate. Management cautions all readers that the forward-looking statements contained in thispresentationarenotguaranteesof futureperformance,andwecannotassureany reader thatsuchstatementswillbe realizedor the forward-looking events and circumstances will occur. Actual results may differ materially from those anticipated or implied in the forward- lookingstatementsduetofactorslistedinthe“RiskFactors”sectioninourfilingswiththeU.S.SecuritiesandExchangeCommission(“SEC”)andelsewhereinthosefilings.Theforward-lookingstatementsspeakonlyasofthedatemade,andotherthanasrequiredbylaw,wedonotintendtopubliclyupdateorreviseanyforward-lookingstatementsasaresultofnewinformation,futureeventsorotherwise.Thesecautionarystatementsqualifyallforward-lookingstatementsattributabletousorpersonsactingonourbehalf.

Thispresentationcontainsthefinancialmeasures“EBITDA,”“AdjustedEBITDA,”and“AdjustedEPS,”whicharenotcalculatedinaccordancewithU.S.GAAP.Areconciliationofthenon-GAAPfinancialmeasuresEBITDA,AdjustedEBITDA,andAdjustedEPStothemostdirectlycomparableGAAPfinancialmeasurehasbeenprovidedintheAppendixtothispresentation.

Second Quarter 2020 Highlights

•Allofourbusinessesdeemed“EssentialCriticalInfrastructure”(1).

•Minimal impact from COVID-19 in Q2'20 across all three of ourbusinesssegments.

•OurStrategycontinuestoproduceresultsandreducerisk.

•Wecontinuetoserveallourcustomers.

•RecordEBITDAandstrongoperatingcashflow.

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(1)PertheNationalCybersecurityandInfrastructureAgency

Second Quarter 2020 Results• Revenuesincreasedto$400.0millionfrom$264.1millioninQ2'19,primarilyattributabletotheinclusionofthreemonthsofrevenuefromPlateauoperations.

• Grossmarginincreased524basispointsto14.9%from9.7%inQ2'19.

• EBITDAwas$41.2millioninQ2'20,a169%increaseover$15.3millioninQ2'19.

• Year-to-dategenerated$52.3millionincashfromoperations,comparedtocashburnof$4.3millionand$7.9millioninQ2'19andQ2'18,respectively.

• Cashandcashequivalentswere$70.6millionatquarterend.

• CombinedBacklogandassociatedmarginwere$1.57billionand11.7%atquarterend.

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Backlog Growth And Margin Improvement

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June30,2020 December31,2019 BooktoBurnIn2020Amount Margin% Amount Margin%

Backlog $1,134million 12.9% $1,068million 11.5% 1.11X

CombinedBacklog $1,571million 11.7% $1,342million 11.0% 1.37X

• Backlogreaches$1.13billion,up6%fromtheendof2019.

• Combined Backlog which includes unsigned low-bid awards reaches $1.57billion.

• Backloggrossmarginincreased140bpsto12.9%andCombinedBackloggrossmarginincreased70bpsto11.7%fromendof2019.

Consolidated Results

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($MM) Q22020 Q12020 Q22019

Revenues $400.0 $296.7 $264.1

GrossProfit 59.6 35.2 25.5GrossMargin 14.9% 11.9% 9.7%

SG&A (18.5) (17.6) (10.2)SG&Aas%ofRevenues (4.6)% (5.9)% (3.9)%

IntangibleAssetAmortization (2.9) (2.8) (0.6)

OtherOperatingExpense,net (5.2) (2.7) (3.5)

OperatingIncome 33.0 12.1 11.2

InterestExpense,net (7.5) (7.7) (2.6)

IncomeTaxExpense (7.2) (1.2) (0.7)

Noncontrollinginterest (0.1) (0.1) 0.0

NetIncometoSTRL $18.2 $3.1 $7.8

DilutedEPS $0.65 $0.11 $0.29

EBITDA $41.2 $20.3 $15.3

CashFlowsfromOperatingActivities $41.5 $10.8 $14.9

• Overall variations from 2019 were driven by the October 2, 2019acquisition of Plateau and the related acquisition refinancing andchangesinthetaxNOLaccountinginQ42019.

• TheQ22020grossmarginimprovementoverQ12020wasdueto:

◦ AhighermarginmixofworkandhighervolumesforPlateau;

◦ Seasonally slow firstquarter revenues results inahigher levelofunderabsorbedfixedcosts;and,

◦ Improved gross profits and margins in each of Sterling's legacyunits;HeavyCivil,CommercialandResidential.

• TheincreaseinQ22020OtherOperatingExpensewasdrivenbyahighermixofgrossprofitgeneratedbySterling's50%ownedsubsidiarieswhichresultedinanincreasedamountofincomesharingexpense.

• Theeffectiveincometaxratein2020is28%,ofwhichthecashportionisexpectedtobe6%,essentiallyStateincometaxes.Theeffectiveincometaxratein2019of8%reflectstheimpactoftheNOLutilization.

Segment Results

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• HeavyCivil

◦ Revenuesincreased10%reflectingtheincreasingbacklog.◦ Grossprofitandgrossmarginimprovedyearoveryear.◦ Thedecrease inoperating incomewas the resultof increasedgrossprofit from

our50%owned subsidiarieswhichdrovehighermargins, but alsodrovehighermembers interest expense of $1.8M. Heavy Civil also had additional costsassociatedwithCOVID-19pandemicimpactsduringthequarter.

• SpecialtyServices

◦ RevenuesfromPlateautotaled$105.6millionbenefitingfromitsrecordbacklogatthebeginningofthequarterandpoorMarch2020weatherpushingworkintoQ22020.

◦ Commercialrevenuesincreased8%to$30.1million.◦ OperatingincomeandmargingrowthweredrivenbytheinclusionofPlateau.

• Residential

◦ RevenuesincreasedasheavyraininMarch2020pushedworkintoQ22020.◦ Houstoniscontinuingtogainscaleandaccountedfor14%oftheslabvolumein

Q22020comparedto6%inQ22019.◦ Second quarter COVID-19 related impact was not as severe as its customers

expectedatthebeginningofQ22020.◦ Operating margins improved with the continued ramp-up of our Houston

expansion.

($MM) Q22020%of

RevenueQ22019

%ofRevenue

Revenue

HeavyCivil $220.4 55% $200.2 75%

SpecialtyServices $135.7 34% $27.9 11%

Residential $43.9 11% $36.0 14%

TotalRevenue $400.0 $264.1

OperatingIncome

HeavyCivil $3.9 1.8% $5.7 2.9%

SpecialtyServices $23.2 17.1% $0.9 3.1%

Residential $6.0 13.8% $4.8 13.4%

Subtotal $33.2 8.3% $11.4 4.3%

Acquisitionrelatedcosts $(0.1) $(0.3)

TotalOperatingIncome $33.0 8.3% $11.2 4.2%

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Increased EBITDA and Cash Flow Drives De-levering Strategy

October2019FiveYearCreditFacility(the"Facility")

• $400MTermLoanFacility

• $75MRevolvingCreditFacility

• Facilityproceedsof$400MtoacquirePlateauonOctober2,2019

• Facility structured to reduce total funded debt EBITDA coveragefromaninitial3.5Xto2.5Xorlesscoveragebytheendof2021.

• NopenaltyforFacilityprepayments.

KeycashflowConsiderations

• Cashflowsfromoperationswere$52.3MforthesixmonthsendedJune30,2020comparedto$(4.3)Mforthecomparableprioryearperiod.

• 2020 EBITDA guidance of $125M to $135M; Actual EBITDA of$61.5Mforthesixmonthsof2020.

• Additional2020noncashexpensesexpectedtobeinthe$25Mto$29Mrange(NOLutilization,stockbasedcompensation,noncashinterestexpense,etc.).

• Scheduleddebtpaymentstotal$52Min2020and$50Min2021.

• Morecashflowmodelingconsiderationsprovidedintheappendix.

EBITDAcoveragetargetedtobe2.5Xorlessbytheendof2021

• RecordCombinedBacklogandmargin inBacklogatquarterend,despiteCOVIDrelatedheadwinds.

• SolidliquiditypositionthatcontinuestostrengthenthroughouttheremainderoftheyearwithcontinuedstrongEBITDAandcashflowgeneration.

• Aresilientteamthathasshowntheabilitytoadjustquickly inarapidchangingenvironment.

• COVIDimpactstoourend-markets,specificallywithinourResidentialspace,havebeenlessseveretodatethananticipated.Goingforwardwedonotforeseeanymajor hurdles to clear in relation to COVID-19. However, with the continuingvolatility of the COVID-19 pandemic, significant incremental pandemic impactscouldkeepusfromachievingour2020guidance.

Forward Looking Business Fundamentals Remain Strong

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Reinstating 2020 Guidance

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• WenowexpectFY2020revenuesofbetween$1.415billionand$1.430billion.◦ This26%projectedrevenuegrowthisaresultofouryear-to-dateperformance,theanticipatedcontributionfrom

Plateau,andourrecordhighCombinedBacklog,alongwithourviewoncurrentbookingtrendsandmarketstrength.

• 2020 adjusted net incomemid-point guidance of $42.5million, growing 73%or $18.0millionover2019.◦ AttributabletoafullyearofcontributionfromPlateau,recordhighCombinedBacklogmargin,continuedmixshift

tohighervalueaddprojects,andimprovedprojectexecution.◦ Adjustednetincomeguidanceincludesaneffectiveincometaxrateofapproximately28%.Thisrateincludesnon-

cashincometaxexpenseofapproximately$12.8million($0.46perdilutedshare).

• Mid-pointexpectedadjustedEBITDAof$130.0million.◦ MorethandoubleFY2019adjustedEBITDA.◦ Reflectstheabovefactorsthatinfluencebothrevenueandnetincome.

• Mid-pointexpectedadjusteddilutedEPSof$1.52.◦ Assuming28milliondilutiveweightedaveragesharesoutstanding.

Contact Us

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RonBallschmiedeChiefFinancialOfficer281-214-0777

FredBuonocore,CFASeniorVicePresident212-836-9607fbuonocore@equityny.com

MikeGaudreauAssociate212-836-9620mg@equityny.com

CompanyRepresentativeSterlingConstructionCompany,Inc.

InvestorRelationsAdvisorsTheEquityGroupInc.

Appendix

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Strategy Driving Profitable Growth

13Dollaramountsinmillions

Revenue $1,415-$1,430

GrossMargin 13%-14%

G&AExpenseas%ofRevenue 5%

OtherExpenseNet $14-$16

JVNon-ControllingInterestExpense $1.5-$2

AdjustedNetIncome** $41-$44

AdjustedDilutedEPS** $1.46-$1.57

ExpectedDilutiveSharesOutstanding 28.0million

14*DollarsinmillionsexceptfordilutiveEPS**Excludes$1-$2millionofnon-recurringacquisitionrelatedexpense

Modeling Considerations*

Modeling Considerations* (Continued)

DepreciationandAmortization $34-$36

CAPEX(netofdisposals) $25-$30

AdjustedEBITDA** $125-$135

EffectiveIncomeTaxRate*** 28%

15*Dollarsinmillions**Excludes$1-$2millionofnon-recurringacquisitionrelatedexpense***Oftheexpense,only$4.6millionisanticipatedtobecashtaxes

ThreeYearRevenueGrowthExpectations:

HeavyCivil–HardBid 2%-3%

HeavyCivil–AlternativeDelivery 3%-5%

SpecialtyServices 5%-7%

Residential 5%-6%

Modeling Considerations - Cash Flow

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NON-CASHITEMS Q22020YTD Q22019YTD

Depreciation $10.8 $7.3

IntangibleAmortization $5.7 $1.2

DebtIssuanceCostAmortization $1.8 $1.6

Stock-basedCompensation $6.2 $1.7

FederalIncomeTaxes $6.2 $0.8

FY2020Expectations FY2019

$23to$24 $15.9

$11to$12 $4.8

$3-$4 $3.4

$10to$12 $3.8

21%ofPretaxIncome Nil

OTHERITEMS Q22020YTD Q22019YTD

InterestExpense,includingDebtIssuance $15.4 $6.0

CAPEX,netofDivestitures 13.8 4.1

ChangesinnetOperatingAssetsandLiabilities(2) $0.4 $(26.1)

FY2020Expectations FY2019

$30to$31 $16.7

$25to$30(1) $14.1

Nil $(3.9)

(1)WiderangeasactualspendingisdependentonhowtheCOVID-19uncertaintiesplayoutforthebalanceof2020.(2)WhileSterlingwillexperiencequarterlyseasonalvariationsthroughout2020,wedonotanticipateasignificantchangeforthefullyear.

($MM)

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