Some applications call for deeper than standard joist depths. It can be as simple as needing additional space to accommodate large HVAC or plumbing systems. Or it can be technical, such as the need to support heavier loads or longer spans.

Fortunately, not only does Boise Cascade EWP offer deep depth BCI® Joists, our 18ʺ BCI 60 Joist and 18ʺ and 20ʺ BCI 90 Joist are now inventoried in our Eastern distribution locations for improved availability.

So why are deep depth Boise Cascade® BCI Joists often a good choice for floors and roofs, particularly for multi-family projects?

There are many, but the most common reasons architects and builders choose deep depth joists are:

• Ability to support heavier loads 
• Longer span capabilities
• Less restrictive spacing requirements
• Stiffer floor/roof performance
• Allow for larger holes in the web for HVAC and plumbing

A Different Approach to Fire Suppression

In addition to the performance enhancing features above, some Boise Cascade deep depth joists provide an added advantage for fire suppression applications.

Because some deep depth joists (specifically, BCI 90, AJS® 25 and AJS 30 Joist series) feature larger flanges, they only require one layer of gypsum board or mineral wool insulation to provide a 1-hour fire floor/ceiling assembly for Type IIIA and VA construction.

The result is an effective, often more affordable, approach to meeting code requirements.

Learning More

Boise Cascade offers five different deep depth joist series greater than 16” deep available across North America. There are several ways for you to learn more about how they might work for your multi-family project:

• Contact your local Boise Cascade representative
• Download our Western, Eastern and AJS I-Joist Commercial Design Guides
• Spec and analyze a deep depth joist in our BC Software suite products

Remember: Web stiffeners are required at all bearing locations for joist depths of 18″ and deeper.