Subject
Customer
Location
Job No.
Engr.
Rev.
Date
Page

Wind Load Report - Roof Truss Wind Load

1. Site & Building Data

Roof Type: Gable  
Wind Speed (ult): 130 mph
Exposure Category: C  
Enclosure Class: Enclosed  
Building Width (W): 33 ft.
Building Length (L): 53 ft.
Eave Height (he): 9 ft.
Foundation Height (hf): 0 ft.
Roof Pitch: 4 /12
Eave Overhang (OHe): 0 ft.
Gable Overhang (OHg): 0 ft.

2. Parameters & Coefficients

Topographic Factor (Kzt): 1.0
Directionality Factor (Kd): .85
Roof Angle (θ): 18.43 deg.
Mean Roof Height (h): 11.75 ft.
Ridge Height (hr): 14.50 ft.
Pos. Internal Pressure (+GCpi): +0.18  
Neg. Internal Pressure (-GCpi): -0.18  
Velocity Pressure Exp. Coeff. (Kh): 0.85 @ z=h
Velocity Pressure (qh): 31.22 psf
End Zone Width (a): 3.00 ft.
Zone 2/2E Dist.: 16.50 ft.

3. Design Assumptions and Notes

Code Standard: ASCE 7-10
Geometry: Regular-Shaped Bldg.
Height Class: Low-Rise Building
Notes:

4. Design Loads

Top Chord Dead Load: 5 psf
Bottom Chord Dead Load: 10 psf
Truss/Rafter Spacing: 24 in. o/c

4. Design Wind Pressures: MWFRS Envelope Procedure


Load Case A: Transverse Direction
Surface GCpf Design Pressure (psf)
(w/ +GCpi) (w/ -GCpi)
1 0.52 10.50 21.74
2 -0.69 -27.16 -15.92
3 -0.47 -20.25 -9.01
4 -0.42 -18.59 -7.35
1E 0.78 18.74 29.97
2E -1.07 -39.02 -27.78
3E -0.67 -26.64 -15.40
4E -0.62 -24.91 -13.68
a) (+) and (-) signs signify wind pressures acting toward & away from surfaces.
b) External Pressure Coefficients linearly interpolated from Fig. 28.4-1 ASCE 7-10.
c) Design building for all wind directions, 4 load patterns per load case.
d) Total horizontal shear shall not be less than that by neglecting roof wind forces.
e) Min. wind load for enclosed or partially enclosed bldg.: 16 psf wall, 8 psf roof.
f) Design pressures are for strength design, multiply by 0.6 for ASD.
Wind Loads Maseeh Rezazadah 339 West River Road, Palatka, FL 32177 23
Engineer Name ENGINEERING COMPANY INC.
Street Address City, CA 99999
ph. (800) 000-0000    www.website.com 		-
4/23/2025 1
Subject
Customer
Location
Job No.
Engr.
Rev.
Date
Page

Load Case B: Longitudinal Direction
Surface GCpf Design Pressure (psf)
(w/ +GCpi) (w/ -GCpi)
1 -0.45 -19.67 -8.43
2 -0.69 -27.16 -15.92
3 -0.37 -17.17 -5.93
4 -0.45 -19.67 -8.43
5 0.40 6.87 18.11
6 -0.29 -14.67 -3.43
1E -0.48 -20.60 -9.37
2E -1.07 -39.02 -27.78
3E -0.53 -22.16 -10.93
4E -0.48 -20.60 -9.37
5E 0.61 13.42 24.66
6E -0.43 -19.04 -7.80
a) (+) and (-) signs signify wind pressures acting toward & away from surfaces.
b) External Pressure Coefficients linearly interpolated from Fig. 28.4-1 ASCE 7-10.
c) Design building for all wind directions, 4 load patterns per load case.
d) Total horizontal shear shall not be less than that by neglecting roof wind forces.
e) Min. wind load for enclosed or partially enclosed bldg.: 16 psf wall, 8 psf roof.
f) Design pressures are for strength design, multiply by 0.6 for ASD.


Torsional Load Cases
Surface Load Case GCpf Design Pressure (psf)
(w/ +GCpi) (w/ -GCpi)
1T A - 2.63 5.44
2T A - -6.79 -3.98
3T A - -5.06 -2.25
4T A - -4.65 -1.84
5T B - 1.72 4.53
6T B - -3.67 -0.86
a) (+) and (-) signs signify wind pressures acting toward & away from surfaces.
b) Pressures designated with a "T" are 25% of full design wind pressures.
c) Torsional loading shall apply to all 8 load patterns using the figures shown.
d) Design pressures are for strength design, multiply by 0.6 for ASD.
e) Torsional Design Exceptions: One story bldg. with h ≤ 30 ft,
   Two stories or less framed with light frame construction,
   Two stories or less with flexible diaphragms.
Wind Loads Maseeh Rezazadah 339 West River Road, Palatka, FL 32177 23
Engineer Name ENGINEERING COMPANY INC.
Street Address City, CA 99999
ph. (800) 000-0000    www.website.com 		-
4/23/2025 2
Subject
Customer
Location
Job No.
Engr.
Rev.
Date
Page

5. Wind Load Calculations


1.) Lateral Loads - Transverse Direction:


Lateral Loads on Roof Diaphragm with Positive Internal Pressure
53 ft.
6.00 ft.
47.00 ft.
67.3 plf
50.2 plf
50.6 plf
28.4 plf
1597 lbs
1484 lbs
87.9 plf
66.8 plf
128.8 plf
89.6 plf
a) (-) signs signify wind lateral forces acting opposite to the direction of the arrows shown.
b) Strength design values multiplied by 0.6 to obtain ASD values.



Wind Base Shear (ASD)
Load Case A: Transverse Direction
Load Case Walls (lbs) Roof (lbs) Roof Overhangs (lbs) Total Lateral Load (lbs) R1 (lbs) R2 (lbs)
Positive Internal Pressure 4399 -1318 0 3081 1597 1484
Negative Internal Pressure 4399 -1318 0 3081 1597 1484
Roof Pressure = 0 4399 0 0 4399 2304 2095
Min. Pressures (8 psf, 16 psf) 2290 1399 0 3689 1844 1844
a) Bottom half of wall neglected in tributary area calculations.
b) Strength design values multiplied by 0.6 to obtain ASD values.
Wind Loads Maseeh Rezazadah 339 West River Road, Palatka, FL 32177 23
Engineer Name ENGINEERING COMPANY INC.
Street Address City, CA 99999
ph. (800) 000-0000    www.website.com 		-
4/23/2025 3
Subject
Customer
Location
Job No.
Engr.
Rev.
Date
Page

2.) Lateral Loads - Longitudinal Direction:


Lateral Loads on Roof Diaphragm with Positive Internal Pressure
33 ft.
3.00 ft.
30.00 ft.
51.4 plf
39.6 plf
36.2 plf
18.5 plf
29.2 lbs
174.5 lbs
392.6 lbs
586.4 lbs
1640 lbs
1551 lbs
a) (-) signs signify wind lateral forces acting opposite to the direction of the arrows shown.
b) Strength design values multiplied by 0.6 to obtain ASD values.
c) Where the length of building (L) exceeds 4X the mean roof height (h), wind drag forces should additionally be considered.



Wind Base Shear (ASD)
Load Case B: Longitudinal Direction
Load Case Walls (lbs) Gable Ends (lbs) Roof (lbs) Total Lateral Load (lbs) RA (lbs) RB (lbs)
Positive Internal Pressure 2008 1183 0 3190 1640 1551
Negative Internal Pressure 2008 1183 0 3190 1640 1551
Roof Pressure = 0 2008 1183 0 3190 1640 1551
Min. Pressures (8 psf, 16 psf) 1426 871 0 2297 1148 1148
a) Bottom half of wall neglected in tributary area calculations.
b) Strength design values multiplied by 0.6 to obtain ASD values.
Wind Loads Maseeh Rezazadah 339 West River Road, Palatka, FL 32177 23
Engineer Name ENGINEERING COMPANY INC.
Street Address City, CA 99999
ph. (800) 000-0000    www.website.com 		-
4/23/2025 4
Subject
Customer
Location
Job No.
Engr.
Rev.
Date
Page

3.) Roof Truss Reactions:


Roof Truss/Rafter Reactions: Transverse End Zone
409 lbs
286 lbs
Max. Horz. ① = 111 lbs
Max. Uplift ① = 409 lbs
a) Strength design values multiplied by 0.6 to obtain ASD values.
b) Windward loads may be positive or negative depending on pitch of roof.



Roof Truss/Rafter Reactions (ASD)
w/ Positive Internal Pressure
Load Case Horizontal Load (lbs) Gross Uplift (lbs) Net Uplift (lbs) U1 (lbs) U2 (lbs)
Transverse Int. Zone 46 939 334 201 133
Transverse End Zone 82 1300 695 409 286
Longitudinal Int. Zone 66 878 273 186 87
Longitudinal End Zone 111 1211 607 387 220
a) Gross Uplift calculations do not include any counteracting roof dead loads.
b) Net Uplift calculations include counteracting roof dead loads multiplied by 0.6 per load case (7) ASCE 7-10.
c) Strength design values multiplied by 0.6 to obtain ASD values for wind loads.
d) Loads based on truss spacing calculated at 24" o/c.
e) Negative values for horizontal load indicate load acting in windward direction (tranverse load cases).
f) Negative values for uplift indicate net downward force (zero uplift).













*Disclaimer: The calculations produced herein are for initial design and estimating purposes only. The calculations and drawings presented do not constitute a fully engineered design. All of the potential load cases required to fully design an actual structure may not be provided by this calculator. For the design of an actual structure, a registered and licensed professional should be consulted as per IRC 2012 Sec. R802.10.2 and designed according to the minimum requirements of ASCE 7-10. The wind load calculations provided by this online tool are for educational and illustrative purposes only. Medeek Design assumes no liability or loss for any designs presented and does not guarantee fitness for use.
Wind Loads Maseeh Rezazadah 339 West River Road, Palatka, FL 32177 23
Engineer Name ENGINEERING COMPANY INC.
Street Address City, CA 99999
ph. (800) 000-0000    www.website.com 		-
4/23/2025 5