A carpenter is preparing to install tongue-and-groove (T&G) subfloor panels. Which of the following is the most critical step to ensure a quiet and stable subfloor system?

Question: A carpenter is preparing to install tongue-and-groove (T&G) subfloor panels. Which of the following is the most critical step to ensure a quiet and stable subfloor system?

Answer options:

• Nailing the panels only around the perimeter of the room.
• Leaving a 6 mm gap between the panel ends and the wall sheathing. ✅ Applying a continuous bead of approved construction adhesive to the top edge of all joists before laying panels.
• Staggering panel end joints by at least 150 mm (6 inches) in adjacent rows.

Correct answer: Applying a continuous bead of approved construction adhesive to the top edge of all joists before laying panels.

Explanation: Applying a generous, continuous bead of approved construction adhesive to the joists before laying T&G subfloor panels is crucial. This bonds the subfloor directly to the joists, preventing movement that causes squeaks and enhancing the floor system's stiffness. While staggering joints and leaving expansion gaps are important, adhesive is key for squeak prevention.