Stagger subfloor end joints and leave a 1/8-inch gap at the square ends

Stagger end joints at least 4 ft row-to-row (running bond) — stacked joints make a weak seam that telegraphs through the finish floor. Leave a 1/8″ gap at the SQUARE end joints only; the T&G long edges self-gap.

What this diagram shows

A plan-view comparison of subfloor panel layout. On the left, the wrong way: panel end joints are stacked in the same line row to row, creating a continuous seam that weakens the floor diaphragm and telegraphs through the finish flooring. On the right, the correct running-bond layout: end joints are offset at least 4 feet between adjacent rows for a stiff, quiet floor. A magnified detail shows that a one-eighth-inch expansion gap belongs at the square end joints only, because the tongue-and-groove long edges self-gap.