SWI-T Joist Design Properties

Series^1	Depth (in)	Weight (plf)	Allowable Moment^2@ 100% (ft - lb)	Allowable Shear^2,3@ 100% (lb)	Maximum End Reaction^3	EI x 10^6(in^2 - lb)	GA x 10^5(lb)
SWI-24	9-1/2"	1.9	2105	900	900	133	4.9
SWI-24	11-1/4"	2.1	2725	1000	1000	211	6.4
SWI-24	11-7/8"	2.2	2920	1000	1000	238	6.9
SWI-24	14"	2.3	3590	1000	1000	344	8.6
SWI-24S	14"	2.3	3590	1300	1300	344	8.6
-	-	-	-	-	-	-	-
SWI-34	9-1/2"	2.6	3405	1000	1000	216	4.9
SWI-34	11-1/4"	2.8	4400	1200	1200	340	6.4
SWI-34	11-7/8"	2.9	4725	1200	1200	385	6.9
SWI-34	14"	3.0	5795	1200	1200	556	8.6
SWI-34	16"	3.2	6815	1100	1100	747	10.1
SWI-34S	14"	3.0	5795	1500	1500	556	8.6
SWI-34S	16"	3.2	6815	1700	1700	747	10.1
-	-	-	-	-	-	-	-
SWI-44S	18"	4.1	10450	1900	1900	1291	11.7
SWI-44S	20"	4.3	11815	2100	2100	1620	13.3

NOTES:

1. Series SWI-24 flanges are 2 x 2 inches (51 mm x 51 mm), Series SWI-34 flanges are 2 x 3 inches (51 mm x 76 mm) and Series SWI-44 flanges are 2x4 inches (51 mm x 102 mm).
2. Moment and shear values and end reactions are for normal duration of load and are permitted to be increased in accordance with Chapter 16 of the 1994 Uniform Building Code (UBC).
3. Allowable shear and end reactions are shown without web stiffeners. The Suffix "S" indicates a web stiffener is required.
4. Maximum end reaction is based on 2 inch (51 mm) bearing length for 24 Series Joists and 2-1/2" (64 mm) bearing length for 34 and 44 Series Joists.

5. Deflection calculations must include both bending and shear deformation. The formulas above shall be used to determine total deflection.

Deflection due to Uniform Loads:
Defl. = (22.5WL⁴/EI) + (1.5PL/GA)

Deflection due to Concentrated Load at Joist Center Span:
Defl. = (36PL³/EI) + (3PL/GA)

W = The uniform load in pounds per lineal foot.
L = The effective length (span of joist) in feet.
EI = The product of the moment of inertia and modulus of elasticity as given in SWI-Joist design properties.
P = The concentrated load in pounds.
GA = Product of the shear modulus of the web material and the web area between the joist flanges as given in SWI-Joist design properties.
Defl. = Deflection in inches, resulting from the application of the above formulas.

SWII-Header Design Properties

Series	Depth (in)	Weight (plf)	Allowable Moment @ 100% (ft - lb)	Allowable Shear @ 100% (lb)	EI x 10^6(in^2 - lb)	GA x 10^5(lb)
SWII-42	7-1/4"	3.7	2081	1170	134	7.1
SWII-42	9-1/4"	4.3	2934	1610	240	10.5
SWII-42	11-1/4"	4.6	3801	2050	378	13.9
-	-	-	-	-	-	-
SWII-62	7-1/4"	4.8	3270	1170	209	7.1
SWII-62	9-1/4"	5.4	4610	1610	377	10.5
SWII-62	11-1/4"	6.0	5972	2050	378593	13.9

NOTES:

1. Deflection of uniformly loaded, simple span SWII-Headers may be calculated as:

Defl. = (22.5WL⁴/EI) + (1.5WL²/GA)

Where:

W = Uniform Load (plf).
L = Clear Span (ft).
EI = The product of Modulus of Elasticity and Moment of Inertia.
GA = The product of Shear Modulus of the web material and the web area between the joist flanges.
Defl. = Deflection in inches.

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