Interpretation #: CEB-2021-38-2020 IRC-R502.8.2

Building or Fire Safety Law Interpreted

675 IAC 14-4.4 2020 Indiana Residential Code Section R502.8.2 Engineered wood products. Cuts, notches and holes bored in trusses, structural composite lumber, structural glue-laminated members, cross-laminated timber members or I-joists are prohibited except where permitted by the manufacturer's recommendations or where the effects of such alterations are specifically considered in the design of the member by a registered design professional.

Issue

Whether written statements from the manufacturer, contained outside of installation instructions, may qualify as "manufacturer's recommendations" for purposes of permitting cuts, notches, and holes in the listed engineered wood products, under Section R502.8.2 of the 2020 Indiana Residential Code (IRC).

Interpretation of the State Building Commissioner

Yes. Under Section R502.8.2 of the 2020 IRC, the location or manner of the manufacturer's recommendation is not limited to the products' installation instructions. Their recommendations permitting such alterations may be provided in other forms of communication.

Rationale

In the absence of evidence that the alterations were considered by a registered design professional, the code states that alterations to engineered wood products are allowable only when permitted by the manufacturer's "recommendation". Since the code sometimes refers to practices (including alterations) being allowed only when permitted by the manufacturer's installation instructions, the fact that the term "installation instructions" is absent from this section indicates the manufacturer's recommendation may appear in communications other than installation instructions. In addition to the code section itself, the ICC's commentary also fails to mention installation instructions, saying only:

In short, the manufacturer must provide use recommendations that the proposed alterations have been deemed structurally acceptable, or a design professional must be involved. The code is silent on the specific form that the "use recommendation" must take. There is no requirement that it appear in the installation instructions.

Note that this interpretation does not address instances in which it is unclear from the manufacturer's written material whether they permit cuts, notches and holes or not, and in which there is no written approval or support for these alterations by a registered design professional. In such instances, it is up to the authority having jurisdiction to determine whether the manufacturer has permitted such alterations.