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Willie Thompson Jr Engineering Letter4/23/2025 Client:BlueRavenSolar 1403NorthResearchWay,BuildingJ Orem,UT84097 RE: 6.9kWSolarPVArrayInstallStructuralCertificationLetter ThompsonResidence 15801104thAveSE Yelm,WA98597 AHJ:Yelm ToWhomItMayConcern: ScopeofWork: 2. ProvidedInformation: BuildingDesignCriteria: FramingDescription: ThebelowtableisadescriptionoftheframingbasedontheinformationthatwasprovidedbyBlueRavenSolar: ArrayName(s) Slope Span MetalplateconnectedpreǦmanufacturedtrusses spacedat24in.o.c.with2x4topandbottomchords, and2x4webs. CompositionShinglewith PlywoodDecking 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: Evaluatetheconnectioncapacityoftheproposedrackingandsystemtotheexistingroofstructure. MP1&2 27 7'Ǧ0" P(roof)=25psf 2021IBC/IRC,ASCE7Ǧ16 II 7psf(MP1&2) 20psf(Liveloadisremoveddirectlyunderpanels) 110mph(Vult),ExpC 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 Thescopeofthisreportisstrictlylimitedtoanevaluationofthefastenerattachment,underlyingframingandsupporting structureonly.Allpanels,rackingandhardwareshallbeinstalledpermanufacturerspecificationsandwithinspecifieddesign limitations.Allwaterproofingshallbeprovidedbythemanufacturer.DomusStructuralEngineering,LLCassumesnoresponsibility formisuseorimproperinstallationofthesolarPVpanelsorracking. NoneMP1&2 (2)#14woodscrewswith1.75inchmin. embedmentdepthintoframing. SFMButyl (Framing)Railless Results Upgrade(ifrequired)ArrayName(s) AdequatetosupporttheimposedloadingǦNo structuralupgradesrequired RackingMethod Staggered MaximumSpacing (Landscape/Portrait) 72in.L/48in.P Fastener P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page2of9 Digitally signed by John A. Calvert Date: 2025.04.23 13:08:01 -06'00' DeadLoadsCalculations 4psf 2psf 0.7 psf 0psf 0.3 psf 7psf PVSystemDeadLoad RoofDeadLoadAdjustedto27 degRoofSlope RoofDeadLoad VaultedCeilingǦN/A Miscellaneous TotalRoofDeadLoad 2x4TopChords (MP1&2) Item Load CompositionShingle PlywoodDecking Item Load PVSystemDeadLoadWeight ProvidedbyClient/Manufacturer 3psf PVSystemDeadLoadAdjustedto 27degRoofSlope 3.4 psf 7.9 psf 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 0.72 Fig.7.4Ǧ1 34 Calculations: =Eq.7Ǧ1 = 17.5 19.3 psf =Eq.7.4Ǧ1 = 17.5 13.8 psf = Sec.7.3.4 =N/AN/Apsf 25.0 psf *Designsnowequalsgroundsnow,snowreductionsnotpermittedperAHJ 1 *SeeAttachmentCapacityCalculationsforDemand/CapacityRatio ShedsSnow Effective/TribWindArea(ft2) RoofSlope 27 Portrait Lateral(SFMButyl(Framing)) Landscape 23.70 27 PanelOrientation 22.67 LateralSnowLoadonStandoff (lbs)257.3 269.0 IȉPgor20psfmin FlatRoofSnowLoad,pf SlopedRoofSnowLoad,Ps MinimumLowǦSlopeRoofSnowLoad (ifrequired) = DesignRoofSnowLoad,proof = No DesignSnowLoad psf25.025.0 LocalMinimumRoofSnowLoad,pminAHJ N/AN/A psf (MP1&2) Thesnowloadsonthestandoffs,theirattachment,andtheunderlyingstructurearedeterminedpertherequirementsof ASCE7Ǧ16Chapter7orgivendirectlybytheAHJ. 0.7ȉCeȉCtȉIȉPg CsȉPg 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 = 27 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) 68.0 34.0 34.0 47.4 23.7 23.7 68.0 Effective/TribWindArea(ft2)22.67 11.33 7.56 23.70 11.85 7.90 22.67 PressureEqualizationFactor,Ja 0.68 0.78 0.80 0.67 0.78 0.80 0.68 ExternalPressureCoefficient,GCp Ǧ1.47 Ǧ2.44 Ǧ3.15 Ǧ1.46 Ǧ2.42 Ǧ3.11 0.56 DesignWindPressure(Ult)(psf)Ǧ23.72 Ǧ45.29 Ǧ59.78 Ǧ23.31 Ǧ44.52 Ǧ59.18 16.00 DesignWindPressure(ASD)(psf)Ǧ14.23 Ǧ27.18 Ǧ35.87 Ǧ13.99 Ǧ26.71 Ǧ35.51 10.00 DeadLoadonAttachment(lbs) 68.0 34.0 22.7 71.1 35.6 23.7 68.0 AttachmentNetUpliftForces(ASD)(lbs)Ǧ282 Ǧ288 Ǧ257 Ǧ289 Ǧ295 Ǧ266 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 = 288 lbs 295 lbs = 425 lbs 425 lbs = *SeeWindLoadsCalculations = 288 lbs 295 lbs = = = 1.75 in 1.75 in = 150 lb/in 150 lb/in = 1.6 1.6 = 840 lbs 840 lbs = Lateral/SnowChecks = 257 lbs 269 lbs = 426 lbs 426 lbs = *SeeSnowLoadsCalculations 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 DCR<100%ThereforeOK DCR<100%ThereforeOK PanelOrientation PanelOrientation 68% 69% 34% 35% Results Results Results 60% 63% Landscape DurationofLoadFactor(Wind) MaximumDesignUplift(ASD)* StandoffUpliftCapacity(Manufacturer) StandoffDemand/CapacityRatio,DCR Portrait StandoffDemand/CapacityRatio,DCR MaximumDesignLateral(ASD)* StandoffLateralCapacity(Manufacturer) FastenerAllowablePullout,W EmbedmentDepth,T P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page6of9 BeamCalculations PASS DeadLoad 7.9 psf PVLoad 3.4 psf SnowLoad 25.0 psf in LiveLoad 20.0 psf in3 in4 Slope 27 deg Cantilever N/A ft Span1 7ft Span2 N/A ft TotalLength 7ft AnalysisMethod TotalLoad 36.3 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 DeflectionCriteria 207 0.524 1785 LL TL 75.8% 84.6%0.665 0.397 N/A 1740 Bending(Ǧ) Deflection: 1785 (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 An a l y s i s Be a m Lo a d i n g 0.786 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 35.0% 97.5% N/A P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page7of9 Element UnitWeight(psf) Area/Length Weight(lbs) Roof 7.9 2450.0ft^2 19247.9 Ceiling 6.0 2450.0ft^2 14700.0 ExteriorWalls 11.0 198.0ft 17423.1 InteriorWalls 8.0 99.0ft 6335.7 57707 Element UnitWeight(psf) Area(Sq.Ft.) Weight(lbs) PVSystem 3 335.8 1007.3 1007.3 Weight(lbs) 5770.7 1007.3 1.7% OK LateralCheckofExistingLateralForceResistingSystems Per10%lateralexemptionof2021IEBCSection805.3 ExistingWeightofAffectedBuilding TotalPVSystemWeight Element (8'WallHeightAssumed) PertheInternationalExistingBuildingCode(IEBC)2021Section805.3,alterationsto abuildingthatresultinlessthan10%increaseinthetotalweightmaybeperformed withoutalateralevaluationoftheexistingbuilding.Thechecksaboveshowthatthe totaladditionalweightaddedduetotheproposedPVarraywillnotincreasethe totalweightofthebuildingbymorethan10%,thusqualifyingunderSection805.3. ExistingRoofSeismicWeight NewPVSystemSeismicWeight 10%Comparison Results PercentIncrease ApproximateWeightofPVSystem(Actual) 10%ofExistingBuildingWeight(Allowable) 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