PE Calcs Stamped - Rogovin RebeccaFreedom Forever LLC
43445 Business Park Dr Suite 110
Temecula, CA 92590
Attn.: To Whom It May Concern
re job:ROGOVIN, REBECCA
18 WINSLOW AVE,
NORTHAMPTON, MA 01062
Design Criteria:
Code:2015 IBC w/ 780 CMR
ASCE 7-10
Live Load:20 psf
Ult Wind Speed:117 mph
Exposure Cat:B
Ground Snow:40 psf Min Roof Snow:35
Current Renewables Engineering Inc.
Professional Engineer
info@currentrenewableseng.com
1/11/2021
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 mounting equipment shall be designed and installed per manufacturer's approved installation
specifications.
Date :1/11/2021
Job Code: ROGOVIN, REBECCA
2 of 6
Roof Properties:
Roof Type =
Roof Pitch (deg) =
Mean Roof Height (ft) =
Attachment Trib Width (ft) =
Attachment Spacing (ft) =
Framing Type =
Framing Size =
Framing OC Spacing (in.) =
Section Thickness, b (in.) =
Section Depth, d (in.) =
Section Modulus, Sx (in.^3) =
Moment of Inertia, Ix (in.^4) =
Framing Span (ft) =
Deflection Limit D+L (in.) =
Deflection Limit S or W (in.) =
Attachments Pattern =
Framing Upgrade =
Sister Size =
Wood Species =
Wood Fb (psi) =
Wood Fv (psi) =
Wood E (psi) =
CD (Wind) =
CD (Snow) =
CLS =
CM = Ct = CL = Ci =
CF =
Cfu =
Cr =
F'b_wind (psi) =
F'b_snow (psi) =
F'v_wind (psi) =
F'v_snow (psi) =
M_allowable_wind (lb-ft) =
M_allowable_snow (lb-ft) =
V_allowable_wind (lbs) =
V_allowable_snow (lbs) =
E' (psi) =
1139 725
1700000 1700000
1246 582
1584 1008
207 207
1734 810
1977 2281
288 288
1.15 1.15
2751 3174
1.3 1.5
1.00 1.00
1.15 1.15
1.0 1.0
1.6 1.6
1.15 1.15
180 180
1700000 1700000
DF #1 DF #1
1000 1000
Adequate Adequate
NA NA
1.07 0.80
Fully Staggered Fully Staggered
8 6
1.6 1.2
7.6 3.1
20.8 5.4
1.5 1.5
5.5 3.5
2x6 2x4
24 24
4 4
Rafter Truss
13 13
1.65 1.65
Metal Metal
12 30
Roof 1 Roof 2
Date :1/11/2021
Job Code: ROGOVIN, REBECCA
3 of 6
Load Calculation:
Panels Dead Load (psf) =
Roofing Weight (psf) =
Decking Weight (psf) =
Framing Weight (psf) =
Misc. Additional Weight (psf) =
Existing Dead Load (psf) =
Total Dead Load (psf) =
Ground Snow Load, pg (psf) =
Min Flat Snow, pf_min (psf) =
Min Sloped Snow, ps_min (psf) =
Snow Importance Factor, Ic =
Exposure Factor, Ce =
Thermal Factor, Ct =
Flat Roof Snow, pf (psf) =
Slope Factore, Cs =
Sloped Roof Snow, ps (psf) =
Ultimate Wind Speed (mph) =
Directionality Factor, kd =
Topographic Factor, kzt =
Velocity Press Exp Factor, kz =
Velocity Pressure, qz (psf) =
External Pressure Up, GCp_1 =
External Pressure Up, GCp_2 =
External Pressure Up, GCp_3 =
External Pressure Down, GCp =
Design Pressure Up, p_1 (psf) =
Design Pressure Up, p_2 (psf) =
Design Pressure Up, p_3 (psf) =
Design Pressure Down, p (psf) =16.0 17.7
-32.3 -24.0
-51.1 -24.0
0.45 0.85
-17.7 -19.8
-1.55 -1.15
-2.45 -1.15
-0.85 -0.95
0.70 0.70
20.9 20.9
117
0.85
1.0
Roof 1 Roof 2
35 35
Wind Load Calculations:
35 35
1.00 1.00
Roof 1 Roof 2
1.2 1.2
Snow Load Calculations:
40
35
NA
1.0
0.9
5.9 5.6
8.9 8.6
0.9 0.6
1.0 1.0
2.0 2.0
2.0 2.0
Dead Load Calculations:
3.0
Roof 1 Roof 2
Date :1/11/2021
Job Code: ROGOVIN, REBECCA
4 of 6
Hardware Checks:
Attachment Type =
Allowable Up Force (lbs) =
Allowable Down Force (lbs) =
Allowable Side Force (lbs) =
Applied Uplift Force (lbs) =
Uplift DCR =
Applied Down Force (lbs) =
Down DCR =
Applied Lateral Force (lbs) =
Lateral DCR =
Roof Framing Checks:
LC1: D+S
Applied Moment (lb-ft) =
Applied Shear (lbs) =
Allowable Moment (lb-ft) =
Allowable Shear (lbs) =
Moment DCR =
Shear DCR =
LC2: D+0.6W
Applied Moment (lb-ft) =
Applied Shear (lbs) =
Allowable Moment (lb-ft) =
Allowable Shear (lbs) =
Moment DCR =
Shear DCR =
LC3: D+0.75(S+0.6W)
Applied Moment (lb-ft) =
Applied Shear (lbs) =
Allowable Moment (lb-ft) =
Allowable Shear (lbs) =
Moment DCR =
Shear DCR =
LC4: 0.6D+0.6W
0.39 0.32
0.21 0.25
1734 810
1584 1008
678 257
339 257
0.17 0.14
0.09 0.11
1734 810
1584 1008
297 115
148 115
0.56 0.45
0.31 0.36
1246 582
1139 725
352 262
Force Checks:
Roof 1 Roof 2
703 262
0.32 0.77
0.57 0.51
52 125
0.55 0.40
245 220
162 162
-116 -85
210 210
431 431
Attachment Checks:
Roof 1 Roof 2
S5! Seam Clamp S5! Seam Clamp
Date :1/11/2021
Job Code: ROGOVIN, REBECCA
5 of 6
Applied Moment (lb-ft) =
Applied Shear (lbs) =
Allowable Moment (lb-ft) =
Allowable Shear (lbs) =
Moment DCR =
Shear DCR =
LC1: D+L
Deflection (in.) =
Deflection Limit (in.) =
Deflection DCR =
LC2: S
Deflection (in.) =
Deflection Limit (in.) =
Deflection DCR =
LC3: W (Down)
Deflection (in.) =
Deflection Limit (in.) =
Deflection DCR =
LC4: W (Up)
Deflection (in.) =
Deflection Limit (in.) =
Deflection DCR =
Seismic Check:
Wall Weight (psf) =
Tributary Wall Area (ft2) =
Total Wall Weight (lbs) =
Roof Weight (psf) =
Roof Area (ft2) =
Total Roof Weight (lbs) =
Total Existing Weight (lbs) =
PV Panel Weight (lbs) =
Number of Panels =
Total Additional PV Weight (lbs) =
Additional PV Weight:
54
28
1525
1200
20400
6
3500
20809
41209
0.03 0.01
Existing Weight:
17
-0.04 -0.01
1.23 0.92
1.23 0.92
0.03 0.01
0.15 0.05
0.04 0.01
0.18 0.04
1.23 0.92
1.84 1.38
0.04 0.01
Deflection Checks (Service Level):
Roof 1 Roof 2
0.07 0.02
0.05 0.05
0.03 0.04
1734 810
1584 1008
84 40
42 40
Date :1/11/2021
Job Code: ROGOVIN, REBECCA
6 of 6
(Existing W + Additional W)/(Existing W) =104%
The increase in weight as a result of the solar system is less than 10% of the existing structure and
therefore no further seismic 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 the engineering consulting firm 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.
Weight Increase: