ROOF PANELS ALLOWABLE POSITIVE AND CONNECTION LOADS (PSF)
CFR PANEL
DIMENSIONS
DESIGN
CRITERIA
SUPPORT SPAN (FEET)
2.5
3.0
4.0
5.0
6.0
7.0
42" WIDE, 2" THICK
BENDING & SHEAR
141.3
115.8
84.8
66.8
55.1
46.9
DEFLECTION (L/240)
176.4
143.2
101.2
75.7
58.6
46.4
CONNECTION
39.8
38.1
34.8
31.5
28.2
24.2
42" WIDE, 2.5" THICK
BENDING & SHEAR
163.2
133.8
97.8
76.8
63.2
53.7
DEFLECTION (L/240)
204.5
167.0
119.7
91.0
71.6
57.7
CONNECTION
48.7
46.0
40.6
35.2
29.8
25.6
42" WIDE, 3" THICK
BENDING & SHEAR
182.9
150.1
109.7
86.0
70.7
60.0
DEFLECTION (L/240)
229.3
188.0
136.0
104.4
83.1
67.8
CONNECTION
57.6
53.9
46.4
38.9
31.5
27.0
42" WIDE, 4" THICK
BENDING & SHEAR
195.2
160.6
117.7
92.3
75.6
64.0
DEFLECTION (L/240)
249.6
205.8
150.7
117.2
94.8
78.6
CONNECTION
75.4
71.1
62.5
53.9
45.4
36.8
42" WIDE, 5" THICK
BENDING & SHEAR
222.1
183.2
134.6
105.7
86.6
73.2
DEFLECTION (L/240)
283.5
234.4
172.5
135.1
110.0
91.9
CONNECTION
75.4
71.1
62.5
53.9
45.4
36.8
42" WIDE, 6" THICK
BENDING & SHEAR
246.1
203.4
149.8
117.8
96.6
81.6
DEFLECTION (L/240)
313.7
259.8
192.0
151.0
123.4
103.6
CONNECTION
75.4
71.1
62.5
53.9
45.4
36.8
Based on CFR-42 panel with 24 ga. exterior face (min Fy = 50 ksi) and 26 ga. interior face (min Fy = 33 ksi).
Based on attachment with CFR panel clip with (3) 1/4"-14 Self-Drilling Tek 3 screws in min. 14 gage steel or (2) 1/4"-14 Self-Drilling Tek 3 screws in min. 12 gage steel. In lieu of self-drilling screws, self-tapping screws may be used.
Allowable positive load is the lowest value of panel bending strength, shear strength & deflection limit.
Allowable suction load is the lowest value of panel bending strength, shear strength, deflection limit and connection strength.
Connection loads will increase with interior back fastening. Consult Metl-Span for loads and fastening patterns.
The loads based on panel stress and deflection design criteria are derived from ASTM E-72 structural testing. The allowable loads are calculated with a factor of safety of 2.5 and 3.0 for bending and shear stresses, respectively, and deflection limitation of L/240.
The panel and its connection strength was determined from ASTM E1592 testing, and the allowable loads are calculated with a factor of safety of 2.0.
The clip fastener capacity was determined from manufacturer fastener pullout data, and the allowable loads are calculated with a factor of safety of 3.0.
The structural capacity of the purlins are not considered and must be examined independently.
Reference to multiple spans is based on conditions of 3 or more spans.
For SI: 1 foot = 305 mm, 1 psf = 47.9 Pa, 1 inch = 25.4 mm.
Insulation Effectiveness
Insulation
Thickness
Operating
Temperature
Thermal
Conductivity
(K-Factor)
Heat Transfer
Coefficent
(U-Value)
Thermal
Resistance
(R-Value)
2"
Ambient
.127
.063
16
2.5"
To +40F
.127
.051
20
3"
To +30F
.127
.042
24
4"
+30F to -20F
.127
.031
32
5"
-20F to -50F
.127
.025
40
6"
-50F to -70F
.127
.021
48