When laying out stud spacing for standard 1220x2440 mm (4x8 ft) sheathing, why is 400 mm on centre spacing preferred over 600 mm on centre, particularly for exterior walls?

Question: When laying out stud spacing for standard 1220x2440 mm (4x8 ft) sheathing, why is 400 mm on centre spacing preferred over 600 mm on centre, particularly for exterior walls?

Answer options:

• It uses less material overall
• It provides better sound insulation ✅ It allows for better nailing surfaces for all sheathing edges
• It results in a lighter wall structure

Correct answer: It allows for better nailing surfaces for all sheathing edges

Explanation: 400 mm on centre spacing ensures that all vertical edges of 1220 mm wide sheathing panels land on a stud, providing a continuous nailing surface for proper attachment and structural integrity as per NBC framing requirements.