On Jan 17, 3:41*pm, ransley wrote:
What is the correct spacing for drywall screws for a wall and ceiling,
what I've found so far is 16" wall and 12" ceiling, I can't find
chicago code on this and a dry Waller *doing a few hundred sheets for
me is about 16" on ceilings

USG Gypsum Handbook

http://www.usg.com/documents/constru...k/chapter3.pdf
Page 111

wood framing
single layer drywall attached with nails
ceilings 7" o/c
side walls 8" o/c

When I've done ceilings, I've used ~6" o/c ......results in 1 extra
nail every 4' and it's easier for me to just keeping 1/2'ing the
spacing rather than worrying about 7" spacing.

wood framing
single layer drywall attached with screws
ceilings 12" o/c
side walls 16" o/c

fire rated walls & ceilings have different nail spacing as do shear
walls.

Looks like your installer needs a "do over".

cheers
Bob