As shown in all Boise Cascade literature for Boise I-joists, notching or cutting of the flanges is not allowed. In addition, the joist hole table displays the allowable size and location of holes that may be in the joist web. Both items refer to Boise I-joists that are used as structural members designed to support loads between supports, such as floor joists and roof rafters.
However, the flange notching and hole provisions previously mentioned do not apply when AJS/BCI joists are supported continuously along its length, as is the case with rim joist and blocking applications.
Cutting notches and holes in rim joist and blocking members is sometimes unavoidable in construction for plumbing, anchor bolts, ventilation, etc. Rim joist and blocking members provide resistance to both gravity and lateral (wind and seismic loads). These loads are typically applied along the members’ lengths and not at concentrated points. Thus, moderate size notches and holes do not significantly reduce the capacity of such members to adequately transfer loads. The following drawings detail notch and holes provisions for 16” and shallower AJS/BCI blocking and rim joist.
As required in all AJS/BCI rim joist and blocking applications, concentrated loads from king studs, columns, beams, and other sources require squash blocks to transfer the load away from the AJS/BCI product.
The provisions are intended for Part 9 residential prescriptive lateral design governed by the National Building Code or Canada. In areas of high wind or seismic loads, please consult the design professional of record before cutting or notching rim board, rim joist or blocking members.