Setting the correct cantilever deflection limit depends on using the correct ratio and understanding the difference between the properties in BC Framer® software and the notation used on the Boise Member Report (and BC Calc® software.)

The deflection properties in BC Framer use the straight L/__ format. For example: L/240. This is true both for spans supported at each end and cantilever spans which have support at one end only.

In contrast, the Boise Member Report and BC Calc use a different notation for cantilevers, shown like this: 2xL/__

For example: 2xL/480.

This causes some confusion because the ** input **in BC Framer uses one notation, but the

**is shown in another. They are both showing the same deflection ratio.**

*output*Here is a Live Load Cantilever Ratio setting of L/240 in BC Framer.

A joist designed looks like this on the Boise Member Report. In this case the controlling deflection is at the cantilever end and just barely passes because it meets the 2xL/480 criteria for the Live Load Cantilever Ratio.

The example above illustrates the ** input **in BC Framer, the

**on the Boise Member Report, and the fact that these two ratios are equal:**

*output*L/240 = 2xL/480

48/240 = (2x48)/480 = 96/480

Here is a related article explaining the cantilever deflection ratio in BC Calc.

What does 2xL/480 mean? - The meaning of the "2xL/" deflection control when designing a member with a cantilever.