General
Presented in the Agway Metals Inc. load tables are maximum uniformly distributed specified loads.
The load tables contained on these data sheets were prepared by Dr. R.M. Schuster P.Eng. Professor of Structural Engineering, University of Waterloo, Ontario, Canada.

Limit States Design (LSD)

Strength - Limit States Design principles were used in the development of the load
tables in accordance with CSA-S136-94, Cold Formed Steel Structural Members
and the National Building Code of Canada, 1995. The factored resistance under
consideration, R, must be equal to or greater than the effect of the factored loads, ie., R ›Effect of Factored Loads hence, a short calculation must be carried out to compute the specified live load. See example. (use of Load Tables)
Serviceability - Maximum specified deflection loads given in the tables must be
compared with their respective specified live loads.

Steel
Specifications - Conforms to ASTM A653 Structural Steel;
.Grade 230 MPa (33 ksi)
.Grade 345 MPa (50 ksi)
.Grade 550 MPa (80 ksi).

Finishes - ZFO75(A25) or Z275(G90) AZMI50(AZ50). For heavier galvanizing,
refer to ASTM A525M (A525).

Design Considerations
Strength - The maximum uniformly distributed specified load obtained from the load table must be equal to or greater than the (Specified live load + 0.833 times the specified dead load). Where 0.833 = 1.25/1.5.

Conservative Strength Approach - The maximum uniformly distributed specified
load obtained from the load table must be equal to or greater than (Specified live
load + specified dead load).

Serviceability (Deflection) - The effective moment of inertia for deflection
determination has been calculated at an assumed specified live load stress of 0.6Fy.

Weight/Mass - For simplicity purposes we have shown the weights as G90 /Z275
although Agway Metals Inc. may use galvalume base materials for a number of
their roofing and siding profiles.

Factored Loads - There are tables requiring the use of "factored" loads when checking for strength. This is not practiced by Agway Metals Inc. The difference means the live load must be multiplied by 1.5 and the dead load must be multiplied by 1.25 before adding them together. The resultant "factored" load is then compared to the strength value in the table. "Be Aware"- At first glance, when deck tables based on "factored" loads are compared to Agway Metals Inc. specified load tables, they may appear to have a higher capacity. However, if these "factored" load tables are used in the same way as the previous "working stress" load tables or the new Agway Metals Inc. (LSD) specified load tables, then the selected deck may be seriously overstressed.

Acoustic Deck - For standard RD36 Acoustic Deck, reduce loads in table by 5%.

RD36 Roof Deck (Imperial)

Given:
• Double span continuous,
L = 7.0 ft each span
• Deck thickness, t = 0.036 in.
• L/240 deflection limit
• Bearing length, n = 2 in.
• Specified loads
1) Dead loads (DL)
 a) deck             2 psf
b) superimposed 8 psf
                DL = 10 psf

2) Live load (LL)
                LL = 45 psf

Solution:
Strength
1) Specified loads
[LL + 0.833 DL]
[45 + 0.833 (10)] = 53.3 psf

2) Maximum specified load (from Table under ¡°B¡±) is 63 psf Since 63 > 53.3 ¡à OK

3) Check end web crippling (n = 2 in.)
a) Specified end reaction
0.375(53.3)7.0 = 140 lb/ft

b) Maximum specified end reaction (from section property table)

Pe = Pe1 + Pe2
Pe = 145 + 101 = 898 lb/ft
Since 898 > 140 ¡à OK

Note: The maximum specified
interior reaction is
Pi = Pi1 +Pi2