Force Transfer Around Openings (FTAO)

FTAO is a method of wood shear wall design that uses continuous wood structural panel sheathing (either plywood or OSB) across the entire wall, including around windows and doors.

Flat steel straps and blocking transfer tension and compression forces around openings, allowing the full wall to act as a single shear wall system.

Compared to segmented and perforated shear wall methods, FTAO can accommodate a wider range of wall sizes, narrower piers and multiple openings while requiring fewer hold-downs.

Continuous sheathing also provides practical non-structural benefits: an uninterrupted drainage plane, a continuous nail base for cladding and a stiffer wall that helps prevent stucco cracking.

More versatility: designing with FTAO allows for the use of narrower wall segments while meeting required height-to-width ratios.

A high likelihood that fewer hold-downs will be required.

Using uninterrupted plywood or OSB across the wall face creates a consistent nail base for cladding attachment, an effective air and drainage barrier and a stiffer wall overall.

Tested and code-recognized: FTAO is a codified design method under SDPWS-21 Section 4.3.2, backed by APA laboratory testing and field research validating both force distribution and deflection performance. APA testing also shows that FTAO provides a stronger and stiffer wall design compared to a wall of the same geometry designed using the perforated or segmented method.