Results 1 to 13 of 13
  1. #1
    Terry Sandmeier's Avatar
    Terry Sandmeier Guest

    Default Wavy Drywall Ceiling!

    Good Morning All,

    Has anyone ever seen drywall bow and wave between the trusses on the ceiling before? House was built 1978, 1/2 drywall, truss spacing 24", no obvious signs of was staining or exposure from the roof. My first thought was moisture from condensation over time has softened the drywall to cause it to sag. It is firmly attached to the trusses and that is what you see holding the high point then sagging between. There is about 8" of blown in cellulose insulation on top. This is odd and have not seen it before. I have already written my report noting this and my thoughts but any additional info would be great.

    I thank anyone for their input. T



    Copy023.JPG

    Similar Threads:
    Member Benefits1

  2. #2
    Join Date
    Mar 2007
    Location
    Plano, Texas
    Posts
    4,245

    Default Re: Wavy Drywall Ceiling!

    Yes, I see it every so often, always on 24" joists. Cellulose seems to be involved frequently also.
    Cellulose is a poor choice for this setup IMHO since it is the heaviest per inch. If there is 8" now, there would have been much more in '78, maybe even double that. Throw in high humidity and the Sheetrock is pushed past its limit.

    Jim Luttrall
    www.MrInspector.net
    Plano, Texas

  3. #3
    Join Date
    Aug 2011
    Location
    Bennett (Denver metro), Colorado
    Posts
    1,461

    Default Re: Wavy Drywall Ceiling!

    I wonder if they used 3/8" sheetrock instead of 1/2". I have seen that on rare occasion.

    If you choose not to decide, you still have made a choice.

  4. #4
    Join Date
    Feb 2009
    Location
    Southern Vancouver Island
    Posts
    4,607

    Default Re: Wavy Drywall Ceiling!

    Nowadays, we should warn people that the popcorn texture probably has asbestos in it as well.

    That old drywall will be costly to dispose of.

    John Kogel, RHI, BC HI Lic #47455
    www.allsafehome.ca

  5. #5
    Join Date
    Jan 2011
    Location
    Guelph,Ontario
    Posts
    173

    Default Re: Wavy Drywall Ceiling!

    Quote Originally Posted by John Kogel View Post
    Nowadays, we should warn people that the popcorn texture probably has asbestos in it as well.

    That old drywall will be costly to dispose of.
    See wavey ceilings a lot,spacing to far apart to support drywall at 2 feet on centres,especially if humidity levels are high,gravity takes over.


  6. #6
    Join Date
    Mar 2008
    Location
    Charlotte NC
    Posts
    2,304

    Default Re: Wavy Drywall Ceiling!

    Quote Originally Posted by Lon Henderson View Post
    I wonder if they used 3/8" sheetrock instead of 1/2". I have seen that on rare occasion.
    Most use 1/2" on the walls and 5/8" on the ceilings here.

    The beatings will continue until morale has improved. mgt.

  7. #7
    Terry Sandmeier's Avatar
    Terry Sandmeier Guest

    Default Re: Wavy Drywall Ceiling!

    Thanks for the responses guys!

    Were I am at in CO the humidity is very low, but in the winter times when cold the heat and condensation from the living areas can cause moisture build up at these areas. We have alot of 24" oc truss installations and 1/2 for a single family home is not uncommon either especially with older installations. I think this is a unique scenario but all conditions have contributed to this outcome. As for the asbestos, any house built prior to 1980, I provide my asbestos disclosure and in Colorado if any remodeling is done to a house built prior to this time they have to get an asbestos test and abatement if asbestos is found prior to remodeling.


  8. #8
    Join Date
    Mar 2007
    Location
    Santa Rosa, CA
    Posts
    3,154

    Default Re: Wavy Drywall Ceiling!

    Quote Originally Posted by Vern Heiler View Post
    Most use 1/2" on the walls and 5/8" on the ceilings here.
    That's what I thought too. 1/2" on ceilings if rafters are on 16" centers.

    Department of Redundancy Department
    Supreme Emperor of Hyperbole
    http://www.FullCircleInspect.com/

  9. #9
    Join Date
    Nov 2010
    Location
    CO
    Posts
    48

    Default Re: Wavy Drywall Ceiling!

    Is this above a garage or 2nd level? Might be a symptom of high humidity do to lack of attic ventilation. You sure it's 1/2 inch drywall?


  10. #10
    Terry Sandmeier's Avatar
    Terry Sandmeier Guest

    Default Re: Wavy Drywall Ceiling!

    Jeff, it is on the 2nd level but adaquate ventilation.

    The only requirement I found tor 5/8 drywall is ceiling of the garage with living space above it and has to be 5/8 type X. On the nailing scheduale it can be installed with sheets running perpindicular to the framing.


  11. #11
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Wavy Drywall Ceiling!

    Quote Originally Posted by Jim Luttrall View Post
    Yes, I see it every so often, always on 24" joists. Cellulose seems to be involved frequently also.
    Cellulose is a poor choice for this setup IMHO since it is the heaviest per inch.
    .
    .
    Throw in high humidity and the Sheetrock is pushed past its limit.
    Precisely, except that will also happen with fiberglass batts too, but just not as pronounced as with cellulose - because of the weight difference in the two insulation materials.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  12. #12
    Join Date
    Mar 2008
    Location
    Charlotte NC
    Posts
    2,304

    Default Re: Wavy Drywall Ceiling!

    Quote Originally Posted by Terry Sandmeier View Post
    Jeff, it is on the 2nd level but adaquate ventilation.

    The only requirement I found tor 5/8 drywall is ceiling of the garage with living space above it and has to be 5/8 type X. On the nailing scheduale it can be installed with sheets running perpindicular to the framing.
    I doubt that you can find a requirement that it be flat either!

    The beatings will continue until morale has improved. mgt.

  13. #13
    Join Date
    Aug 2009
    Location
    Michigan
    Posts
    249

    Default Re: Wavy Drywall Ceiling!

    1/2" drywall back then should not have been used for 24" centers. It's in their specs to use 5/8" for 24" centers. That being said, there is a newer board out that is lightweight and can span the 24" just having the 1/2" thickness.

    Randy Gordon, construction
    Michigan Building Inspector/Plan Reviewer

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •