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The moment capacity qualification was carried out using the empirical method in accordance with ASTM D 5055-04 for NJ and NJH joists. At each plant, a minimum of 28 specimens of each joist depth are tested on a quarterly basis to verify the actual capacity versus the design capacity.

The moment capacity qualification testing was carried out using the analytical method in accordance with ASTM D 5055-08a for NJM joists. At the Kelowna plant, 10 specimens at each of the extremes of joist depth were tested for moment capacity confirmation as per Section 6.4.2 of ASTM D 5055-08a.

Qualification tests were used to establish the applicable coefficient of variation, CV_w. The reliability normalization factor from Table 13.2.3.2 of CSA O86 was used to determine the specified strength.

The shear capacity was established by computing the shear capacity for each depth separately as per ASTM D 5055-04 for NJ and NJH joists, and ASTM D 5055-08a for NJM joists. Qualification tests were used to establish the applicable coefficient of variation, CV_w. The reliability normalization factor from Table 13.2.3.2 of CSA O86 was used to determine the specified strength.

Stiffness capacity was tested in accordance with Section 6.5.2 of ASTM D 5055-04 for NJ and NJH joists, and ASTM D 5055-08a for NJM joists. The following formula was used to predict mid-span deflection:

${\Delta }_{\text{deflection}}=\frac{5w{L}^4}{384EI}+\frac{w{L}^2}{K}$

where L = clear span (mm)

w = load (kN/mm)

EI (kN·mm2) and K are taken from Table 4.1.1.

Values are available from the manufacturer’s literature.

Two joist specimens from each joist series were tested for creep performance, as per ASTM D 5055-04 for NJ and NJH joists, and ASTM D 5055-08a for NJM joists. The specimens were loaded to 1.5 times the maximum resistive moment (design) and the average deflection recovery had to exceed 90% of the basic dead-load deflection. The criteria were met by the tested specimens.

Elastic properties of the joist flanges are those of S – P – F #2 lumber (or better graded lumber). Fingerjoined lumber has been qualified through tension testing of 60 specimens and verification bending testing of 56 specimens. The fingerjoined flange lumber design value is maintained through ongoing proof tension testing. The manufacturing of the fingerjoint meets NLGA SPS-1 standards and is verified by the certification agency.

Qualification tests were conducted in accordance with ASTM D 5055-08a on 10 specimens of each depth without stiffeners, and 10 specimens of the extreme depths at the specified bearing lengths for all joist series. The span charts referred to in Section 3(i) are for joists without web stiffeners.

Similar qualification was conducted for intermediate bearing; however, the span charts referred to in Section 3(i) are for simple span applications only.

Revised spans were prepared to demonstrate compliance to the CCMC vibration criteria. In addition, since conventional cross bridging is not recommended by the I-joist industry, additional testing was conducted to demonstrate no adverse effects on the bottom flange/web joint for only the "NJ10-12 Series I-Joists" products.

The PRF adhesive 4001/5830E PRF that is produced by Momentive and complies with CSA-O112.7 is used by AcuTruss in Kelowna, BC.