[CCMC 12412-R] CCMC Canadian code compliance evaluation

When the products are used to support uniform loads only, the installation must be in accordance with the span tables (including vibration criteria⁽²⁾) found in the documents entitled:

1. "Pacific Woodtech™ I-Joists RESIDENTIAL CONSTRUCTION CANADIAN (LSD) TECHNICAL GUIDE PWI 18S, 20S, 32S, 36L, 42S, 52S, and 56L; LPI 18, 20Plus, 32Plus, 36, 42Plus, 52Plus and 56,” December 2022; and
2. "Pacific Woodtech™ LIGHT-FRAME COMMERCIAL, MIDRISE, AND MULTIFAMILY CONSTRUCTION CANADIAN (LSD) TECHNICAL GUIDE PWI 20S, 32S, 36L, 42S, 52S, and 56L; LPI 20Plus, 32Plus, 36, 42Plus, 52Plus and 56,” December 2022.

The product must be installed in accordance with the manufacturer’s installation guidelines noted in the two documents listed above for those applications falling within the scope of the documents. Applications outside the scope of these installation guidelines require engineering on a case-by-case basis.

⁽²⁾ In cases where concrete topping is applied or bridging/blocking is used and joists are installed at the maximum spans, the current vibration criteria may not address all occupant performance expectations. Therefore, the manufacturer should be consulted for span adjustments, if necessary, in these types of installations.

The manufacturer’s pre-engineered details within documents (1) and (2) outlined in the Pacific Woodtech Corporation pre-engineered tables section are limited in scope to building designs where the anticipated loads on the following structural details are not exceeded:

• web stiffener requirements, page 5 of (1) and page 22 of (2)
• floor span tables, pages 6 to 9 of (1) and pages 6 to 15 of (2);
• roof span tables, pages 14 to 17 of (1) and pages 16 to 19 of (2);
• uniform floor load tables, pages 10 to 11 of (1);
• uniform roof load tables, pages 12 to 13 of (1);
• loadbearing cantilever tables, page 18 of (1);
• brick ledge cantilever, pages 18 to 19 of (1); and
• web hole tables, pages 20 to 21 of (1) and pages 20 to 21 of (2).

For structural applications beyond the scope/limitations of the above-referenced publications or when required by the AHJ, the drawings or related documents must bear the authorized seal of a professional engineer skilled in wood design and licensed to practise under the appropriate provincial or territorial legislation. Installations beyond the scope/limitations of the Pacific Woodtech Corporation pre-engineered tables and Pacific Woodtech Corporation pre-engineered installation details sections imply, but are not limited to, the following:

• higher loads/longer spans than the manufacturer’s pre-engineered details;
• concentrated loads;
• offset bearing walls;
• areas of high wind and seismicity;
• stair openings;
• design of supporting wall studs/beams when total load exceeds the NBC 2015 pre-engineered floor/roof joist tables;
• design of supporting foundation footings when total load exceeds the NBC 2015 pre-engineered floor/roof joist tables; and
• fire resistance (see applicable fire-resistance assembly listings for specific joist and adhesives used).

The engineer must design in accordance with CAN/CSA-O86, and may use the "Engineering Guide for Wood-Frame Construction," published by the Canadian Wood Council, as a guide.

The factored resistance and engineering properties for the products must not exceed the values set forth in the Design requirements section.

The ends of all I-joist members used as joists, rafters, and beams must be restrained to prevent rollover. This is normally achieved by attaching a diaphragm sheathing to the top or to the compression edge, and to an end wall or shear transfer panel capable of transferring a minimum unfactored uniform load of 730 N/m or the required shear forces due to wind or seismic conditions. Blocking or cross-bracing with equivalent strength may be used.

The compression edges of all the products’ members used as joists and rafters must be laterally supported at least every 610 mm, except where design is done in accordance with CAN/CSA-O86.

Nailing of the products must be in accordance with the manufacturer’s engineering details provided on a case-by-case basis.

Pacific Woodtech Corporation provides engineering support through either their local distributor or a professional engineer skilled in wood design and licensed to practise under the appropriate provincial or territorial legislation. Pacific Woodtech Corporation may also be consulted in the use of the product.

• Pacific Woodtech Corporation (technical support): 800-515-7570; e-mail: design@pacificwoodtech.com.

Damaged or defective products must not be used, unless repaired in accordance with written instructions from the manufacturer.

This product must be identified with the phrase “CCMC 12412-R” along the side of the product. This CCMC number is only valid when it appears in conjunction with the certification mark of APA-EWS.

The design values obtained from testing to ASTM D5055-08a, “Standard Specification for Establishing and Monitoring Structural Capacities of Prefabricated Wood I-Joists,” as specified in CAN/CSA-O86-09, “Engineering Design in Wood,” and in previous editions is summarized below. The manufacturer’s published pre-engineered joist spans were designed in accordance with CAN/CSA-O86-09

The CCMC Registry of Product Assessments contains opinions on the suitability-for-use of products intended as structural elements in houses. Although historically there has been no need to regulate the structural fire performance of houses, an inherent intent of the National Building Code of Canada (NBC) is that occupants have sufficient time to escape from a house in the event of a fire. There are many factors that may determine whether that intent is achieved. The fire endurance of structural elements may be one. However, its importance may be minimized by other factors such as combustible content load, early warning devices, smoke movement and toxicity, and fire department response time; all contributing to the overall system performance. Research is underway within the NRC Construction Research Centre to determine the critical factors that affect occupant escape from houses.

Some innovative structural products have been used in the marketplace for several years and have gained the confidence of design professionals, code authorities and users with respect to their performance under typical fire scenarios. Some newer products have not been in service long enough to have gained that confidence and may present a more obvious concern.

The minimum fire performance of innovative structural materials, or alternative solutions, as compared to that of the NBC-specified conventional wood-frame construction, or acceptable solution, has been the subject of analysis and discussion for several years among fire officials, provincial and territorial regulators, and AHJs. In fire tests conducted between 2002 and 2008 at the NRC, the innovative structural joist systems tested, and currently in the marketplace (i.e., I-joists, C-channel steel joists, metal-plated wood trusses and metal-web trusses), had a time-to-collapse below the performance of exposed 38 mm × 235 mm (2 × 10) lumber joists.

The CCMC provides this floor fire performance information to the local AHJs across Canada to aid their decision-making on whether the fire performance of floors (i.e., the time to evacuate before failure occurs) for alternative joist systems performs “as well as” the inherent fire performance of exposed 38 mm × 235 mm (2 × 10) lumber joists. As is the case for all innovative products, designers and authorities should exercise judgment in considering the use of innovative structural products for houses. Unless otherwise stated, innovative structural products for houses have not been evaluated in the context of the NBC intent noted above.

Proposed fire protection options

The manufacturer’s fire protection options for its proprietary joists are presented below. The CCMC has reviewed this fire-protection option in comparison to the fire performance of unprotected exposed 38 mm × 235 mm (2 × 10) floor joist system.^{Footnote (1)} The proposed fire-protection option performs “as well as” exposed 38 mm × 235 mm (2 × 10) lumber joists. It should be noted that the NBC exempts single-family houses constructed using conventional wood-frame construction, in accordance with Part 9, from requiring a fire-resistance rating (see Article 9.10.8.10. of Division B of the NBC 2015). The proposed fire-protection option for proprietary alternative floor joists is not to be considered in sprinklered single-family houses or where fire-resistance-rated assemblies are required.

Fire protection options

The following seven (7) options of I-joist floor fire protection alternative solutions are provided by the manufacturer.^{Footnote (2)} These floor assemblies have demonstrated fire performance as good as conventional wood-frame 38 mm × 235 mm (2 × 10) exposed-floor construction.

The details of the following fire protection floor assemblies are outlined in the figures below.

1. Fire Protection of Floors FP-01 − 12.5 mm (1/2 in.) gypsum board attached to bottom of flange;
2. Fire Protection of Floors FP-02 − 12.5 mm (1/2 in.) gypsum board attached directly to web;
3. Fire Protection of Floors FP-03 − 12.5 mm (1/2 in.) gypsum board attached directly to sides of flange;
4. Fire Protection of Floors FP-04 − Mineral wool insulation;^{Footnote (3)}
5. Fire Protection of Floors FP-06 − 12.5 mm (1/2 in.) gypsum board installed on top of the bottom flange;
6. Fire Protection of Floors FP-07 − 15.8 mm (5/8 in.) gypsum board installed on top of the bottom flange;
7. Fire Protection of Floors FP-09 − Rockwool SAFE’n’Sound^® mineral wool insulation.^{Footnote (3)}

Fire protection assemblies

The following floor assembly design (FP-01) is the default alternative solution for all cases and where the manufacturer has not undertaken any specific testing to show equivalency to exposed 38 × 235mm (2 × 10) lumber with proprietary joist fire protection options.

The following fire resistance designs, FP-02 to FP-09, provided by the manufacturer provide fire performance as good as to 38 mm × 235 mm (2 × 10) dimensional lumber exposed floor joists.