Are ceiling joists spaced 32" on center too far apart to hang drywall?

Question

The joists in our bonus room are 32" on center apart. I am worried that there may be issues with the drywall sagging in the middle in the future. Is 32" on center too far apart? If so will I need to add in extra joints to hang the drywall?

Answer 1

16 inch centers always..

Answer 2

Everyone says 16", but around here, 24" is standard. I have seen drywall ceilings put on 32" without problems, but you must use 5/8 drywall, not anything thinner. This is not a code issue as some have claimed. If you really are worried about it, add some 2x4 blocking between the joist, very simple and quick to do that.

Answer 3

16" centers is considered the norm. 24" centers when there is no load above and the builder is cutting costs. I have built houses where

12" centers were spec'ed for long spans and wide open interior spaces. But 32" centers? Is this a timber frame structure where there are larger framing members? That's about the only situation that I can think of where you could have joists spaced that far apart and you'd still meet the code and get a certificate of occupancy.  Or, are these actually collar ties, holding the rafters from spreading? If so, then it is possible that they would be put up every-other rafter for 32" centers.

But, whatever the distance between your joists, you should always put strapping (1 x 4 material) up there and and actually fasten the drywall ceiling to the strapping, not to the joists themselves. Dimensional lumber, such as for those joists, is never going to be absolutely straight and true, if you fasted drywall directly to the joists, you will always get a wavy ceiling.

Run a string, get a little line level that will hang on the string and fasten the 1 x 4 strapping to your joists and shim to make it all level. Consider the long spans between joists, you might consider using 5/4 x 4 strapping, which is available in some locales.

Answer 4

I have to first question this 32" center and secondly wonder if the weight of adding drywall won't adversely effect the load capacity of this structure as it is.  Why don't you send me a couple of photos so I can make a more informed recomendation.

As to your question. . . yes, you will likely have problems with sag if not eventual failure if you attach drywall with framing at 32" O/C.  If there is enough structural integrity to accomadate this project I would strongly suggest you strip the ceilings using 1X4 or metal hat channel.  This way you will provide good framing to support the drywall and you'll be able to effectively level the installation by stringing/lasering and shims.

Mike Lonergan

TradesProfessional, Inc.

Answer 5

it actually depends on the weight of the roof, the pitch,...psf... but you can add some blocking in between the joists to strengthen the framing of the roof

Answer 6

I coul be wrong, but I thought it should be 16"-24"

Answer 7

Absolutely!  There is a reason why they are set at 16" on center...for bearing weight loads........( not just for load bearing walls)  The measurement is taken from center of board to center of board actually measuring 14 1/2 inches in the center.  Leaving it that way could be cause for not passing building codes and inspections.   Find your center and put the other board in.  It will SAG!

Answer 8

I have never seen 32" o/c joists spacing used in construction. but if you want to hang drywall you should get some 1X4 strapping and nail them on perpendicular to your joists at 16" o/c  then hang your drywall

Answer 9

generally code is 16" on center... your scenario is WAY to wide and it will sag, and you will have wasted your time and money putting up this sheertock.  As you were thinking, hang another stud inbetween the existing ones and then sheetrock the room... it will last a lifetime that way, and be done right the first time.  16" on center also allows you to nail the sheet along the edges of the 4x8 sheet, preventing sagging and non-supported joints.  (5x16 = 48")