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Charles Perez Engineering letter2/18/2025 Client:BlueRavenSolar 1403NorthResearchWay,BuildingJ Orem,UT84097 RE: 3.87kWSolarPVArrayInstallStructuralCertificationLetter PerezResidence 14902PrairieVistaLoopSE Yelm,WA98597 AHJ:CityofYelmWA ToWhomItMayConcern: ScopeofWork: 2. ProvidedInformation: BuildingDesignCriteria: FramingDescription: ThebelowtableisadescriptionoftheframingbasedontheinformationthatwasprovidedbyBlueRavenSolar: ArrayName(s) Slope Span MetalplateconnectedpreǦmanufacturedtrusses spacedat24in.o.c.with2x4topandbottomchords, and2x4webs. CompositionShinglewithOSB Decking DomusStructuralEngineering,LLC.wasaskedtoprovideastructuralreviewoftheprojectattheabovereferencedaddressfor theproposedinstallationofroofǦmountedsolarpanels.Thescopeofthisreportisstrictlylimitedtotheitemslistedbelowand basedonthebuildingdesigncriteria. Thefindingsofthisreportarebasedonajobsiteevaluationoftheexistingframingsystemwiththeinformationgatheredby BlueRavenSolarasarequestofDomusStructuralEngineering,LLC.Allattachedstructuralcalculationsarebasedonthe providedinformation.Ifroofassemblyhasbeenalteredsincethisinitialobservation,contractorshallnotifyengineerpriorto startingconstruction. DetermineiftheexistingroofframingisstructurallysufficienttosupportthenewPVsysteminadditiontothe coderequireddesignloads. 1. FramingDescription RoofMaterial GroundSnowLoad: Seismic: Pg=20psf SeismiccheckrequiredasSs>=.4andSDCisDorgreater BuildingCodesandStandards: RiskCategory: DeadLoads: RoofLiveLoads: WindSpeed&Exposure: Roof/SlopedSnowLoads: Evaluatetheconnectioncapacityoftheproposedrackingandsystemtotheexistingroofstructure. MP1 23 7'Ǧ6" P(roof)=14psf 2021IBC/IRC,ASCE7Ǧ16 II 7psf(MP1) 20psf(Liveloadisremoveddirectlyunderpanels) 110mph(Vult),ExpC P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page1of9 FramingResults: Belowisasummarytableoftheresultsoftheanalysisandadescriptionofupgradesifrequired. Anchorage: Belowisasummaryofthetypeofconnection(s)thatisproposedtobeusedandtheallowablespacings. Attachment Name 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,LLCassumesno responsibilityformisuseorimproperinstallationofthesolarPVpanelsorracking. NoneMP1 (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 Calvert Date: 2025.02.18 14:57:13 -07'00' DeadLoadsCalculations 4psf 2psf 0.7 psf 0psf 0.3 psf 7psf PVSystemDeadLoad RoofDeadLoadAdjustedto23 degRoofSlope RoofDeadLoad VaultedCeilingǦN/A Miscellaneous TotalRoofDeadLoad 2x4TopChords (MP1) Item Load CompositionShingle OSBDecking Item Load PVSystemDeadLoadWeight ProvidedbyClient/Manufacturer 3psf PVSystemDeadLoadAdjustedto 23degRoofSlope 3.3 psf 7.6 psf P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page3of9 SnowLoadsCalculations SnowDesignParameters: WithoutPV WithPV GroundSnowLoad,pg =2020psf ImportanceFactor,I= 1 1 ThermalFactor,Ct =11.1Table7Ǧ3 ExposureFactor,Ce =11Table7Ǧ2 RoofSurfaceType = AllOtherSurfaces Unobstructed Slippery Surface RoofSlopeFactor,Cs = 1.00 0.78 Fig.7.4Ǧ1 34 Calculations: =Eq.7Ǧ1 = 14.0 15.4 psf =Eq.7.4Ǧ1 =14.012.1psf =Sec.7.3.4 =N/AN/Apsf 14.0 psf 1 *SeeAttachmentCapacityCalculationsforDemand/CapacityRatio ShedsSnow Effective/TribWindArea(ft2) RoofSlope 23 Portrait Lateral(SFMButyl(Framing)) Landscape 22.30 23 PanelOrientation 22.60 LateralSnowLoadonStandoff (lbs)123.6 122.0 IȉPgor20psfmin FlatRoofSnowLoad,pf SlopedRoofSnowLoad,Ps MinimumLowǦSlopeRoofSnowLoad (ifrequired) = DesignRoofSnowLoad,proof = No DesignSnowLoad psf12.114.0 LocalMinimumRoofSnowLoad,pminAHJ N/AN/A psf (MP1) 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= 25ft VelocityPressureExposureCoefficient,Kz = 0.95 Table26.10Ǧ1 RoofSlope = 23 degrees RoofType = Gable ArrayEdgeFactor,Je =1Section29.4.4 EffectiveWindArea = StandoffTributaryarea(seebelow) Calculations: VelocityPressure,qh(Ult)=0.00256ȉKzȉKztȉKeȉV2 Eq.26.10Ǧ1 VelocityPressure,qh(Ult)=0.00256ȉKzȉKztȉKdȉKeȉV2 Eq.26.10Ǧ1 = 24.89 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 Ǧ1.47 Ǧ2.44 Ǧ3.15 Ǧ1.47 Ǧ2.45 Ǧ3.16 0.57 DesignWindPressure(Ult)(psf)Ǧ24.89 Ǧ47.53 Ǧ62.70 Ǧ25.02 Ǧ47.77 Ǧ62.89 16.00 DesignWindPressure(ASD)(psf)Ǧ14.93 Ǧ28.52 Ǧ37.62 Ǧ15.01 Ǧ28.66 Ǧ37.73 10.00 DeadLoadonAttachment(lbs) 67.8 33.9 22.6 66.9 33.5 22.3 67.8 AttachmentNetUpliftForces(ASD)(lbs)Ǧ297 Ǧ302 Ǧ270 Ǧ295 Ǧ300 Ǧ267 267 *SeeAttachmentCapacityCalculationsforDemand/CapacityRatio Portrait Landscape Uplift Thewindloadsonthestandoffsandtheirattachmenttotheunderlyingstructurearedeterminedpertherequirementsfor rooftopsolarpanelsparalleltotheroofsurface(ASCE7Ǧ16,Section29.4.4). (MP1) SFMButyl(Framing) P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page5of9 AttachmentCapacityCalculations UpliftCalculations = 302 lbs 300 lbs = 425 lbs 425 lbs = *SeeWindLoadsCalculations = 302 lbs 300 lbs = = = 1.75 in 1.75 in = 150 lb/in 150 lb/in =1.6 1.6 = 840 lbs 840 lbs = Lateral/SnowChecks = 124 lbs 122 lbs = 426 lbs 426 lbs = *SeeSnowLoadsCalculations NumberofFasteners,N FastenerUpliftCapacity StandoffLateralCheck Portrait LandscapePanelOrientation 2 (MP1) 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 71% 70% 36% 36% Results Results Results 29% 29% 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 7.6 psf PVLoad 3.3 psf SnowLoad 14.0 psf in LiveLoad 20.0 psf in3 in4 Slope 23 deg Cantilever N/A ft Span1 7.5 ft Span2 7.5 ft TotalLength 15 ft AnalysisMethod TotalLoad 30.9 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 1.251111111225 Fb+(psi)= 900 1.25 1 1 1 1.5 1 1.15 1 1941 FbǦ(psi)= 900 1.25 1 1 0.986 1.5 1 1.15 1 1914 E(psi)= 1600000 111111111600000 Emin(psi)= 580000 11111111580000 DeflectionCriteria 225 0.407 1914 LL TL 40.0% 54.5%0.296 0.163 1703 958 Bending(Ǧ) Deflection: 1941 (MP1) 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 0.543 Criteria: Demand Allowable 83 DL+LL Shear Bending(+) L/240 L/180 CreepFactor 1.5 GoverningLoadComboBe a m Cr i t e r i a MultiǦSpan Live Total Demand/Allowable 36.8% 49.4% 89.0% P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page7of9 Element UnitWeight(psf) Area/Length Weight(lbs) Roof 7.6 1874.7ft^2 14256.4 Ceiling 6.0 1874.7ft^2 11248.4 ExteriorWalls 11.0 173.2ft 15240.9 InteriorWalls 8.0 86.6ft 5542.2 46288 Element UnitWeight(psf)Area(Sq.Ft.)Weight(lbs) PVSystem 3 189.0 567.0 567.0 Weight(lbs) 4628.8 567.0 1.2% OK LateralCheckofExistingLateralForceResistingSystems Per10%lateralexemptionof2021IEBCSection805.3 ExistingWeightofAffectedBuilding TotalPVSystemWeight Element (8'WallHeightAssumed) PertheInternationalExistingBuildingCode(IEBC)2021Section805.3,alterationsto abuildingthatresultinlessthan10%increaseinthetotalweightmaybeperformed withoutalateralevaluationoftheexistingbuilding.Thechecksaboveshowthat thetotaladditionalweightaddedduetotheproposedPVarraywillnotincreasethe 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'sbestprofessionaljudgmentbasedupon industrystandards. Ɣ ResolveanyconflictsonthedrawingswithDomusStructuralEngineering,LLCbeforeproceedingwithconstruction. Ɣ Thedesigncriteriausedforthisproject&listedonthefirstpageofthereportisbasedontheengineer'sbest judgementand/orprovidedbytheATCcouncil.AHJspecificrequestsmaydiffer.Pleasecontactourteamifthe designcriterianeedstobemodified. Ɣ AsitevisitwasnotphysicallyconductedbyDomusStructuralEngineering,LLC.Theaccompanyingcalculationsand certificationareprovidedwiththeunderstandingthatthesitebuildingandconstructionstandardsmeetan acceptablelevelofindustrystandards.Itshallbethecontractor'sresponsibilitytoidentifyanyirregularitiessuchas inconsistentframingconditions,waterdamage,firedamage,cracked,splitornoticeablydeflectingframing members. Ɣ DomusStructuralEngineering,LLCisnotresponsibleforenforcingsafetymeasuresorregulations.Thecontractor shalldesign,construct,andmaintainallsafetydevicesincludingshoringandbracing,andshallbesolelyresponsible forconformingtoalllocal,stateandfederalsafetyandhealthstandards,lawsandregulations.Thecontractorshall takenecessaryprecautionstomaintainandinsuretheintegrityofthestructureduringconstruction.Ifalawsuitis filedbyoneofthecontractor'sorsubcontractor'semployees,oranyoneelse,thecontractorwillindemnify,defend andholdtheownerandDomusStructuralEngineering,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, firedamage,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 guards are requested by the customer,notify Domus Structural Engineering,LLC. P.O.Box560,Broomfield,CO80038|projects@domusstruc.com|Page9of9