Walls: 16" on center (max) along each stud. Ceiling: 12" on center (max) along each joist.
Code basis (IRC Table R702.3.5 / IBC Table 2508.5):
- 1/2" gypsum board on wood framing:
- Walls: Screws ≤ 16" o.c.
- Ceilings: Screws ≤ 12" o.c. (due to gravity/sag risk)
Practical notes:
- Keep screws ≥ 3/8" from panel edges.
- Drive heads slightly below paper surface without tearing it.
- For ceilings, consider 1/2" sag-resistant board or 5/8" if joists are 24" o.c. (but yours are 16").
- No adhesive = more critical to hit spacing exactly.
Pro tip: Snap chalk lines on studs/joists before hanging. Screw the field first, then edges.