HomeMy WebLinkAboutLA205746 - APPROVED - Carey A Grant PE Calcs wStamp 08 23 2022Date: 08/23/2022
Job Number: 9580
Prepared for : Wolf River Electric, 101 Isanti Parkway NE, Isanti, MN 55040
Project.: Carey A Grant , 16003 Estate Ln, Lakeville, MN, v
The following calculations are for the structural engineering design of the photovoltaic panels and are
valid only for the structural info referenced in the stamped plan set. The verification of such info is the
responsibility of others. After review, I certify that the roof structure has sufficient structural capacity for
the applied PV loads. All PV mounting equipment shall be designed and installed per manufacturer's
approved installation specifications.
Engineerinc.io
303 N Glenoaks Blvd Suite 200
Burbank, CA 91502
(747) 333 - 5991
new@engineerinc.io
Date Certified and
Signed: 08/23/2022
303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io
Solar Module Details
Module Type HANWHA
Module Quantity 49
Module Model Number 400 WATT
Design Criteria
Code: 2020 Minnesota Building Code (2018 IBC) ASCE 7-16
Live Load (psf)20
Ult Wind Speed (mph)125
Exposure Cat C
Ground Snow (psf)50
Structure Geometry
Eave Height, he (ft)15 to 20ft
Pitch of main roof (deg)20
Building Length, L (ft)60
Building Width, B (ft)50
Roof Area (Module Area) ft2 3000.00
Standoff(i.e., Roof Mount) Spacing Feet 4`
NOTE: attachments should be installed in a staggered configuratiion to properly destributor loading.
Roof Properties
Roof Geometry type Gable Roof
Roof Type Truss
Roof Pitch (deg)20
303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io
Roofing Type Comp Shingles
Sheathing Type 1/2" OSB Board
Wood species No. 2, Douglas Fir-Larch
Wood Fb (psf)900
Wood Fv (psf)180
Wood E (psf)1600000
Purlin C/C Spacing (in)12
Rafter C/C. Spacing (in.)24
Purlin
Section Thickness, b (in.)2
Section Depth, d (in.)4
Rafter
Section Thickness, b (in.)2
Section Depth, d (in.)4
Maximum Rafter Span (ft)7
Factors
Cd(wind)1.60
Cd(Snow)1.60
CLS 1.15
CM 1
Ct 1
CL 0.75
CF 1.5
Cfu 1
Cv 1
Cr 1
M allowable_wind 413.44
M allowable_snow 297.16
303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io
Dead Load(psf)
Comp Shingles 3.00 psf
1/2" OSB Board 2.00 psf
Insulation 2.00 psf
Total Roof 1DL 7 psf
No. 2, Douglas Fir-Larch 31.00 lb/ft3
Solar Panel DL 3.00 psf
Roof 1
Roof_Dist_DL 7.00 psf
M_Roof_Dist_DL 2493.86
Def_Roof_Dist_DL 1.48
PV_uni_Dist_DL 3.00 psf
M_PV_uni_Dist_DL 10.54
Def_PV_uni_Dist_DL 0.01
Total_Uni_DL 11.00 psf
M_Total_DL 2504.40
Def_Total_DL 1.49
Snow Load(psf)
Ground Snow Load, pg 50
Importance Factor, Ic 1
Thermal Factor, Ct 1
Exposure Factor, Ce 1
Flat roof snow, pF 50
Slope Factor, Cs 1
303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io
Sloped Row Snow, ps 50
Uni_Dist_S 50.00
M_uni_Dist_s 306.25
Def_uni_Dist_S 0.18
Wind Load
Ultimate Wind Speed 125
Directionality Factor,kd 0.85
Topographic factor 1.00
Velocity pressure exposure factor,kz 0.88
Ground Elevation Factor,ke 2.16
Side Wall Width 50
Median Roof Height 129.36
Velocity pressure,qz 29.92
External Pressure Up,GCp_1 -0.7
External Pressure Up,GCp_2 -0.6
External Pressure Up,GCp_3 -1.3
External Pressure Down,GCp -0.18
Design Pressure Up,p_1 -17.51
Design Pressure Up,p_2 -15.01
Design Pressure Up,p_3 -32.52
Design Pressure Up,p -4.50
Uni_Dist_W_up -32.52
M_uni_Dist_W_up -199.19
Def_uni_Dist_W_up -0.12
Uni_Dist_W_down -4.50
303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io
M_uni_Dist_W_down -27.56
Def_uni_Dist_W_down -0.02
Lag Screw Uplift Check (ASD)
5/16" Lag Screw Withdrawl value 205.00 lb/in
Lag Screw Penetration 2.50 in
Roof1 0.6D+0.6W(up z1)1699.566 > 512.5
Roof1 0.6D+0.6W(up z2)1701.066 > 512.5
Framing Check (ASD):
Roof1 uni 1.0D+0.6W 2504.40 > 413.44
Lag Screw Penetration 2734.09 > 413.44
Roof1 0.6D+0.6W(up z1)2810.65 > 297.16
Roof1 0.6D+0.6W(up z2)1383.13 > 413.44
Seismic Check:
Wood 5.00 psf
2x4 Studs @ 16"2.00 psf
Gypsum 3.00 psf
Misc(insulatioon,etc)2.00 psf
Total wall DL 12.00 psf
Total Wall Area (Approx)2590.00 ft2
Total Wall W 31080 lbs
Total Roof DL 7.50 psf
Total Roof Area (Approx)1276.93 ft2
Total Roof W 9576.975 lbs
303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io
OK
PV Panel W 3.00 psf
Area of panel 980.00 ft2
Total Roof W 1381.77 lbs
% increase=(Wadditional)/Wexisting 3.63%
The increase in weight as a result of the solar system is less than 10% of the existing structure and therefore no furtherseismic analysis is required.
Limits of Scope of Work and Liability
Existing structure is assumed to have been designed and constructed following appropriate codes at
time of erection, and assumed to have appropriate permits. The calculations produced are only for the
roof framing supporting the proposed PV installation referenced in the stamped planset and were
completed according to generally recognized structural analysis standards and procedures, professional
engineering and design experience, opinions and judgements. Existing deficiencies which are unknown
or were not observable during time of inspection are not included in this scope of work. All PV modules,
racking, and mounting equipment shall be designed and installed per manufacturer's approved
installation specifications. The Engineer of Record and Engineerinc assume no responsibility for misuse
or improper installation. This analysis is not stamped for water leakage. Framing was determined based
on information in provided plans and/or photos, along with engineering judgement. Prior to
commencement of work, the contractor shall verify the framing sizes, spacings, and spans noted in the
stamped plans, calculations, and cert letter (where applicable) and notify the Engineer of Record of any
discrepancies prior to starting construction. Contractor shall also verify that there is no damaged framing
that was not addressed in stamped plans, calculations, and cert letter (where applicable) and notify the
Engineer of Record of any concerns prior to starting construction. Prior to the commencement of work,
the contractor shall verify the existing roof and framing conditions. Notify Engineerinc and the engineer of
record of any Discrepancies prior to starting construction. Prior to the commencement of work, the
contractor shall inspect framing for any damage such as water damage, cracked framing, etc. and notify
the E.O.R. if any issues are found.These plans/calculations are stamped for structural code compliance
of the roof framing supporting the proposed PV installation reference only. These plans/calculations are
not stamped for water leakage. PV modules, racking, and attachment components must follow
manufacturer guidelines and requirements.
303 N. Glenoaks Blvd Suite #200 Burbank, CA 91502 | (747)333-5991 | new@engineerinc.io