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HILLORIE SMITH Engineering letter7/1/2025 Client:BlueRavenSolar 1403NorthResearchWay,BuildingJ Orem,UT84097 RE: 9.24kWSolarPVArrayInstallStructuralCertificationLetter SmithResidence 9313PrairieWindStSE Yelm,WA98597 AHJ:Yelm ToWhomItMayConcern: ScopeofWork: 2. ProvidedInformation: BuildingDesignCriteria: FramingDescription: ThebelowtableisadescriptionoftheframingbasedontheinformationthatwasprovidedbyBlueRavenSolar: ArrayName(s) Slope Span P(roof)=25psf 2021IBC/IRC,ASCE7Ǧ16 II 7psf(MP1&2) 20psf(Liveloadisremoveddirectlyunderpanels) 110mph(Vult),ExpC Evaluatetheconnectioncapacityoftheproposedrackingandsystemtotheexistingroofstructure. MP1&2 30 7'Ǧ0" DomusStructuralEngineering,LLC.wasaskedtoprovideastructuralreviewoftheprojectattheabovereferencedaddressfor theproposedinstallationofroofǦmountedsolarpanels.Thescopeofthisreportisstrictlylimitedtotheitemslistedbelowand basedonthebuildingdesigncriteria. ThefindingsofthisreportarebasedonajobsiteevaluationoftheexistingframingsystemwiththeinformationgatheredbyBlue RavenSolarasarequestofDomusStructuralEngineering,LLC.Allattachedstructuralcalculationsarebasedontheprovided information.Ifroofassemblyhasbeenalteredsincethisinitialobservation,contractorshallnotifyengineerpriortostarting construction. DetermineiftheexistingroofframingisstructurallysufficienttosupportthenewPVsysteminadditionto thecoderequireddesignloads. 1. FramingDescription RoofMaterial GroundSnowLoad: Seismic: Pg=25psf SeismiccheckrequiredasSs>=.4andSDCisDorgreater BuildingCodesandStandards: RiskCategory: DeadLoads: RoofLiveLoads: WindSpeed&Exposure: Roof/SlopedSnowLoads: MetalplateconnectedpreǦmanufacturedtrusses spacedat24in.o.c.with2x4topandbottomchords, and2x4webs. CompositionShinglewith PlywoodDecking P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page1of9 FramingResults: Belowisasummarytableoftheresultsoftheanalysisandadescriptionofupgradesifrequired. Anchorage: Belowisasummaryofthetypeofconnection(s)thatisproposedtobeusedandtheallowablespacings. AttachmentName Pattern: Whererackingmethodisrailless,attachmentsarelocatedwherepanelsmeet.Otherwise,theattachmentsareconnecteddirectlytotherails. Unlessnotedotherwise,allallowablecantileversarelimitedtothemaximumattachmentspacingdividedby3.(1/3*spacing) Limitations: Pleasecontactmewithanyfurtherquestionsorconcernsregardingthisproject. Sincerely, JohnCalvert,P.E. DomusStructuralEngineering,LLC Staggered MaximumSpacing (Landscape/Portrait) 72in.L/48in.P FastenerRackingMethod ArrayName(s) AdequatetosupporttheimposedloadingǦNo structuralupgradesrequired Results Upgrade(ifrequired) Thescopeofthisreportisstrictlylimitedtoanevaluationofthefastenerattachment,underlyingframingandsupporting structureonly.Allpanels,rackingandhardwareshallbeinstalledpermanufacturerspecificationsandwithinspecifieddesign limitations.Allwaterproofingshallbeprovidedbythemanufacturer.DomusStructuralEngineering,LLCassumesnoresponsibility formisuseorimproperinstallationofthesolarPVpanelsorracking. NoneMP1&2 (2)#14woodscrewswith1.75inchmin. embedmentdepthintoframing. SFMButyl (Framing)Railless P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page2of9 Digitally signed by John A. Calvert Date: 2025.07.01 13:32:18 -06'00' DeadLoadsCalculations 4psf 2psf 0.7 psf 0psf 0.3 psf 7psf 8.1 psf (MP1&2) Item Load CompositionShingle PlywoodDecking Item Load PVSystemDeadLoadWeight ProvidedbyClient/Manufacturer 3psf PVSystemDeadLoadAdjustedto 30degRoofSlope 3.5 psf PVSystemDeadLoad RoofDeadLoadAdjustedto30 degRoofSlope RoofDeadLoad VaultedCeilingǦN/A Miscellaneous TotalRoofDeadLoad 2x4TopChords P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page3of9 SnowLoadsCalculations SnowDesignParameters: WithoutPV WithPV GroundSnowLoad,pg =2525psf ImportanceFactor,I= 1 1 ThermalFactor,Ct = 1 1.1 Table7Ǧ3 ExposureFactor,Ce = 1 1 Table7Ǧ2 RoofSurfaceType = AllOtherSurfaces Unobstructed Slippery Surface RoofSlopeFactor,Cs = 1.00 0.67 Fig.7.4Ǧ1 34 Calculations: =Eq.7Ǧ1 = 17.5 19.3 psf =Eq.7.4Ǧ1 = 17.5 12.8 psf = Sec.7.3.4 =N/AN/Apsf 25.0 psf *Designsnowequalsgroundsnow,snowreductionsnotpermittedperAHJ 1 *SeeAttachmentCapacityCalculationsforDemand/CapacityRatio psf25.025.0 LocalMinimumRoofSnowLoad,pminAHJ N/AN/A psf (MP1&2) Thesnowloadsonthestandoffs,theirattachment,andtheunderlyingstructurearedeterminedpertherequirementsof ASCE7Ǧ16Chapter7orgivendirectlybytheAHJ. 0.7ȉCeȉCtȉIȉPg CsȉPg 278.8 IȉPgor20psfmin FlatRoofSnowLoad,pf SlopedRoofSnowLoad,Ps MinimumLowǦSlopeRoofSnowLoad (ifrequired) = DesignRoofSnowLoad,proof = No DesignSnowLoad ShedsSnow Effective/TribWindArea(ft2) RoofSlope 30 Portrait Lateral(SFMButyl(Framing)) Landscape 22.30 30 PanelOrientation 22.60 LateralSnowLoadonStandoff (lbs)282.5 P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page4of9 WindLoadsCalculations WindDesignParameters: UltimateWindSpeed,(Vult) = 110 mph LocalRequirement RiskCategory = II WindDirectionalityFactor,Kd = 0.85 Table26.6Ǧ1 ExposureCategory = C TopographicFactor,Kzt = 1.00 Table26.8Ǧ1 GroundElevation = 0 ft GroundElevationFactor,Ke = 1.00 Table26.9Ǧ1 MeanRoofHeight,h = 20 ft VelocityPressureExposureCoefficient,Kz = 0.90 Table26.10Ǧ1 RoofSlope = 30 degrees RoofType = Gable ArrayEdgeFactor,Je = 1 Section29.4.4 EffectiveWindArea = StandoffTributaryarea(seebelow) Calculations: VelocityPressure,qh(Ult)=0.00256ȉKzȉKztȉKeȉV2 Eq.26.10Ǧ1 VelocityPressure,qh(Ult)=0.00256ȉKzȉKztȉKdȉKeȉV2 Eq.26.10Ǧ1 = 23.75 psf DesignWindPressures,(Ult) =qhȉGCpȉKdȉJeȉJa Eq.29.4Ǧ7 DesignWindPressures,(Ult) =qhȉGCpȉJeȉJa Eq.29.4Ǧ7 Downward PanelOrientation Both Zone 1(Interior) 2(Edge) 3(Corner) 1(Interior) 2(Edge) 3(Corner) All StandoffspacingxǦdirection(in) 48.0 48.0 32.0 72.0 72.0 48.0 48.0 StandoffspacingyǦdirection(in) 67.8 33.9 33.9 44.6 22.3 22.3 67.8 Effective/TribWindArea(ft2)22.60 11.30 7.53 22.30 11.15 7.43 22.60 PressureEqualizationFactor,Ja 0.68 0.78 0.80 0.68 0.78 0.80 0.68 ExternalPressureCoefficient,GCp Ǧ1.45 Ǧ1.96 Ǧ2.62 Ǧ1.45 Ǧ1.96 Ǧ2.62 0.90 DesignWindPressure(Ult)(psf)Ǧ23.38 Ǧ36.39 Ǧ49.73 Ǧ23.54 Ǧ36.56 Ǧ49.84 16.00 DesignWindPressure(ASD)(psf)Ǧ14.03 Ǧ21.83 Ǧ29.84 Ǧ14.13 Ǧ21.94 Ǧ29.90 10.00 DeadLoadonAttachment(lbs) 67.8 33.9 22.6 66.9 33.5 22.3 67.8 AttachmentNetUpliftForces(ASD)(lbs)Ǧ276 Ǧ226 Ǧ211 Ǧ275 Ǧ225 Ǧ209 267 *SeeAttachmentCapacityCalculationsforDemand/CapacityRatio Portrait Landscape Uplift Thewindloadsonthestandoffsandtheirattachmenttotheunderlyingstructurearedeterminedpertherequirementsfor rooftopsolarpanelsparalleltotheroofsurface(ASCE7Ǧ16,Section29.4.4). (MP1&2) SFMButyl(Framing) P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page5of9 AttachmentCapacityCalculations UpliftCalculations = 276 lbs 275 lbs = 425 lbs 425 lbs = *SeeWindLoadsCalculations = 276 lbs 275 lbs = = = 1.75 in 1.75 in = 150 lb/in 150 lb/in = 1.6 1.6 = 840 lbs 840 lbs = Lateral/SnowChecks = 283 lbs 279 lbs = 426 lbs 426 lbs = *SeeSnowLoadsCalculations DCR<100%ThereforeOK DCR<100%ThereforeOK PanelOrientation PanelOrientation 65% 65% 33% 33% Results Results Results 66% 65% Landscape DurationofLoadFactor(Wind) MaximumDesignUplift(ASD)* StandoffUpliftCapacity(Manufacturer) StandoffDemand/CapacityRatio,DCR Portrait StandoffDemand/CapacityRatio,DCR MaximumDesignLateral(ASD)* StandoffLateralCapacity(Manufacturer) FastenerAllowablePullout,W EmbedmentDepth,T NumberofFasteners,N FastenerUpliftCapacity StandoffLateralCheck Portrait LandscapePanelOrientation 2 (MP1&2) SFMButyl(Framing) DCR<100%ThereforeOK DCR<100%ThereforeOK DCR<100%ThereforeOK DCR<100%ThereforeOK StandoffDemand/CapacityRatio,DCR MaximumDesignUplift(ASD) StandoffFastener 2Ǧ#14WoodScrews 2 StandoffUpliftCheck 2Ǧ#14WoodScrews FastenerUpliftCheck Portrait Landscape P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page6of9 BeamCalculations PASS DeadLoad 8.1 psf PVLoad 3.5 psf SnowLoad 25.0 psf in LiveLoad 20.0 psf in3 in4 Slope 30 deg Cantilever N/A ft Span1 7ft Span2 N/A ft TotalLength 7ft AnalysisMethod TotalLoad 36.6 psf Units psi OK psi OK psi OK in OK in OK NDS4AValues Cd Cm Ct CL Cf Cfu Cr Ci Allowable Fv(psi)= 180 1.151111111207 Fb+(psi)= 900 1.15 1 1 1 1.5 1 1.15 1 1785 FbǦ(psi)= 900 1.15 1 1 1.000 1.5 1 1.15 1 1785 E(psi)= 1600000 111111111600000 Emin(psi)= 580000 11111111580000 An a l y s i s Be a m Lo a d i n g 0.808 Criteria: Demand Allowable 73 DL+SL Shear Bending(+) L/180 L/120 CreepFactor 1.5 GoverningLoadComboBe a m Cr i t e r i a SimpleSpan Live Total Demand/Allowable 35.3% 98.4% N/A (MP1&2) SectionMod 3.06 2x4 5.36 DF#2 24 MemberSize LumberSp/Gr MemberSpacing Me m b e r Pr o p e r t i e s MomentofInertia DeflectionCriteria 207 0.539 1785 LL TL 77.9% 88.1%0.712 0.420 N/A 1756 Bending(Ǧ) Deflection: 1785 P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page7of9 Element UnitWeight(psf) Area/Length Weight(lbs) Roof 8.1 2915.0ft^2 23561.7 Ceiling 6.0 2915.0ft^2 17490.0 ExteriorWalls 11.0 216.0ft 19004.7 InteriorWalls 8.0 108.0ft 6910.8 66967 Element UnitWeight(psf) Area(Sq.Ft.) Weight(lbs) PVSystem 3 441.0 1322.9 1322.9 Weight(lbs) 6696.7 1322.9 2.0% OK PertheInternationalExistingBuildingCode(IEBC)2021Section805.3,alterationsto abuildingthatresultinlessthan10%increaseinthetotalweightmaybeperformed withoutalateralevaluationoftheexistingbuilding.Thechecksaboveshowthatthe totaladditionalweightaddedduetotheproposedPVarraywillnotincreasethe totalweightofthebuildingbymorethan10%,thusqualifyingunderSection805.3. ExistingRoofSeismicWeight NewPVSystemSeismicWeight 10%Comparison Results PercentIncrease ApproximateWeightofPVSystem(Actual) 10%ofExistingBuildingWeight(Allowable) LateralCheckofExistingLateralForceResistingSystems Per10%lateralexemptionof2021IEBCSection805.3 ExistingWeightofAffectedBuilding TotalPVSystemWeight Element (8'WallHeightAssumed) P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page8of9 AppendixA:GeneralNotes GENERAL Ɣ Thecontractorshallverifyalldimensions,propertysetbacks,AHJ/HOACC&R's,elevationsandsiteconditionsbefore startingworkandshallnotifyDomusStructuralEngineering,LLCofanydiscrepancies. Ɣ AllreportconclusionsrepresentDomusStructuralEngineering,LLC'sbestprofessionaljudgmentbaseduponindustry standards. Ɣ ResolveanyconflictsonthedrawingswithDomusStructuralEngineering,LLCbeforeproceedingwithconstruction. Ɣ Thedesigncriteriausedforthisproject&listedonthefirstpageofthereportisbasedontheengineer'sbest judgementand/orprovidedbyASCE.AHJspecificrequestsmaydiffer.Pleasecontactourteamifthedesigncriteria needstobemodified. Ɣ AsitevisitwasnotphysicallyconductedbyDomusStructuralEngineering,LLC.Theaccompanyingcalculationsand certificationareprovidedwiththeunderstandingthatthesitebuildingandconstructionstandardsmeetanacceptable levelofindustrystandards.Itshallbethecontractor'sresponsibilitytoidentifyanyirregularitiessuchasinconsistent framingconditions,waterdamage,firedamage,orcracked,splitornoticeablydeflectingframingmembers. Ɣ DomusStructuralEngineering,LLCisnotresponsibleforenforcingsafetymeasuresorregulations.Thecontractorshall design,construct,andmaintainallsafetydevicesincludingshoringandbracing,andshallbesolelyresponsiblefor conformingtoalllocal,stateandfederalsafetyandhealthstandards,lawsandregulations.Thecontractorshalltake necessaryprecautionstomaintainandinsuretheintegrityofthestructureduringconstruction.Ifalawsuitisfiledby oneofthecontractor'sorsubcontractor'semployees,oranyoneelse,thecontractorwillindemnify,defendandhold theownerandDomusStructuralEngineering,LLCharmlessofanyandallsuchclaims. Ɣ Anyandallwaterproofingshallbeprovidedbythecontractor.DomusStructuralEngineering,LLCisnotresponsible forwaterproofing. Ɣ Allhardwareshallbeinstalledpermanufacturerspecificationsandwithinspecifieddesignlimitations.Domus StructuralEngineering,LLCassumesnoresponsibilityforincorrectlyinstalledhardwareorhardwareinstalledoutside ofthemanufacturerspecifications. USERRELIANCE Ɣ DomusStructuralEngineering,LLCwasengagedbyBlueRavenSolar(Client)toperformthisassessment.Thisreport, andtheinformationtherein,arefortheexclusiveuseoftheClient.Thisreporthasnootherpurposeandshallnotbe reliedupon,orused,byanyotherpersonorentitywithoutthewrittenconsentofDomusStructuralEngineering,LLC. Thirdpartiesthatobtainthisreportortheinformationwithinshallhavenorightsofrecourseorrecoveryagainst DomusStructuralEngineering,LLC,itsofficersoremployees. ROOFMOUNTEDARRAYS Ɣ Ifananalysisofasupportingstructureisincludedinourscopeofwork,thestructuralassessmentonlyappliestothe sectionoftheroofthatisdirectlysupportingtheproposedsolarPVsystem. Ɣ Nostructuralmemberscanbecutforconduit,etc.,unlessspecificallyshown.Obtainpriorwrittenapprovalfor installationofanyadditionalconduit,etc. Ɣ Itisassumedthatastandardqualityofconstructioncarewasusedtoconstructtheoriginalbuilding.Itshallbethe contractor'sresponsibilitytofieldverifyanyandallframingmemberssupportingtheproposedPVarrayarein adequatecondition.ThecontractorshallfieldinspectforsubǦstandardconstructionmeans,signsofdryrot,mold,fire damage,etc.andnotifyengineerifanycompromisedmaterialisfoundonsitepriortostartingconstruction. Ɣ Itisassumedthattherehavebeennoadditionalloads(HVACorMEPequipment,additionallayersofroofing,etc) addedtothebuildingoverthecourseofthestructure'shistory.Thecontractorand/orclientshallverifythiswiththe propertyownerandnotifyDomusStructuralEngineering,LLCifadditionalloadhasbeenaddedtothestructure already. Ɣ Flexibleutilityconnectionsmustbeusedatanybuildingseismicjoint. Ɣ CareshouldbetakentoensurethatPVarraysdonotprecludedrainageofrainwater. Ɣ Unlessotherwisenoted,constructionmaterialshallbeevenlydistributedifplacedonframedfloorsorroofs.Loads shallnotexceedtheallowableloadingforthesupportingmembersandtheirconnections. Ɣ Alllagsorwoodscrewsattheroofshallbestainlesssteelandinstalledwithinthemiddle1/3ofthedimensionalwidth oftheframingmembers. Ɣ Allfastenersshallbeaminimumof6"awayfromanytrusspanelorhingejoints,trussplatesand/ormemberends. Fieldverifylocationoffastenerspriortostartingconstruction.AllfastenersshallbepreǦdrilledtoavoidsplitting existinglumber. Ɣ Unlessotherwisenoted,alllagsinstalledinunderlyingroofframingmembersshallbeembedded(threadedembed)a minimumof2.5''intotheunderlyingframing. Ɣ DomusStructuralEngineering,LLCisnotresponsiblefordownslopeeffectsofsnowsheddingorslidingoffofthePV arraynoranydamagetodownslopedecks,roofs,walkways,landscaping,automobiles,pets,people,etc..Ifsnow guardsarerequestedbythecustomer,notifyDomusStructuralEngineering,LLC. P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page9of9