Results 1 to 21 of 21
  1. #1
    daniel nantell's Avatar
    daniel nantell Guest

    Default deck post in contact with ground

    I wrote up a deck with the post in contact with ground , I wrote it up as not a recommend practice, should maintain clearance between ground and support post, the builder told the owners that he used treated wood and I was ok to sink post in ground. My expercience is even through its treated when it in the ground for a few years it still begins to rot.

    Similar Threads:
    2018 ASHI InspectionWorld

  2. #2
    Join Date
    Mar 2007
    Location
    Santa Rosa, CA
    Posts
    2,479

    Default Re: deck post in contact with ground

    dmn,

    I have a couple of questions.

    First of all, what chemical was it treated with? If it is "ground contact" pressure treated lumber, my understanding is that it should last for decades without significant decay. Around here, ACZA (very dark green, almost black colored) treated lumber can be used in direct and prolonged contact with soil. However, if it is the lighter green or reddish, probably not.

    Another question, is what is the post resting on? If there is no concrete footing or pier block, then what is holding up the deck? If the post is sunk into the soil, then it is more likely to sink/settle.

    Department of Redundancy Department
    http://www.FullCircleInspect.com/

  3. #3
    Join Date
    Mar 2007
    Location
    Spring City/Surrounding Philadelphia area
    Posts
    3,473

    Default Re: deck post in contact with ground

    Maybe the the builder would like to put that in writing for the owners.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  4. #4
    A.D. Miller's Avatar
    A.D. Miller Guest

    Default Re: deck post in contact with ground

    Quote Originally Posted by daniel nantell View Post
    I wrote up a deck with the post in contact with ground , I wrote it up as not a recommend practice, should maintain clearance between ground and support post, the builder told the owners that he used treated wood and I was ok to sink post in ground. My expercience is even through its treated when it in the ground for a few years it still begins to rot.
    DN: It seems that this is what the IRC thinks it should look like:

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  5. #5
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,248

    Default Re: deck post in contact with ground

    Wood posts CAN be in ground contact:

    From the 2006 IRC. (underlining is mine)
    - R319.1.2 Ground contact. All wood in contact with the ground, embedded in concrete in direct contact with the ground or embedded in concrete exposed to the weather that supports permanent structures intended for human occupancy shall be approved pressure-preservative-treated wood suitable for ground contact use, except untreated wood may be used where entirely below groundwater level or continuously submerged in fresh water.

    That said, a post in ground contact STILL requires a proper footing and anchoring to the footing.

    This is from the American Wood Council, their Design for Code Acceptance 6, Prescriptive Residential Deck Construction Guide: http://www.awc.org/Publications/DCA/DCA6/DCA6.pdf

    Scroll down to the Figure 12 on the bottom of page 9.

    Have the builder provide documentation that the treatment of the wood posts meets or exceeds that which is required for ground contact and burial.


    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  6. #6
    A.D. Miller's Avatar
    A.D. Miller Guest

    Default Re: deck post in contact with ground

    Like these from this morning's inspection? .40 CCA pressure-treated is all that is required, and that is what they are. Labels were still stapled to the tops. These are just 12 years old.

    Why do it?

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  7. #7
    Join Date
    Jun 2008
    Location
    Maryland
    Posts
    1,049

    Default Re: deck post in contact with ground

    When they are 4x4's I pay more attention to them. With 6x6's there is much more material so it is less of an issue.

    I look at each situation on a case by case basis.


  8. #8
    Join Date
    Mar 2007
    Location
    Lake Barrington, IL
    Posts
    1,363

    Default Re: deck post in contact with ground

    A.D.

    I don't get the 3rd diagram that shows toe nailing the beam/post connection.

    I don't think that toe nailing is recognized as a positive connection.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    Eric Barker, ACI
    Lake Barrington, IL

  9. #9
    A.D. Miller's Avatar
    A.D. Miller Guest

    Default Re: deck post in contact with ground

    Quote Originally Posted by Eric Barker View Post
    A.D.

    I don't get the 3rd diagram that shows toe nailing the beam/post connection.

    I don't think that toe nailing is recognized as a positive connection.
    EB: You'll have to contact the ICC. It is directly from the 2006 IRC, which I did not write.


  10. #10
    daniel nantell's Avatar
    daniel nantell Guest

    Default Re: deck post in contact with ground

    One of the above post showed x4 post rotten off in 12 years, that has been my expierence, they say its treated and will last 20 years but Ive had them completely destroyed in 10 years, mabe the treating manufacture did a poor job pressure treating the lumber, that why I think its better building practice to keep the wood off the ground, even pressure treated. thanks


  11. #11

    Default Re: deck post in contact with ground

    Clarksville Home Inspection
    JW Goad
    TN License #307 | KY License #2402

  12. #12
    Michael Greenwalt's Avatar
    Michael Greenwalt Guest

    Default Re: deck post in contact with ground

    The issue with treated lumber in contact with the ground doesn't have as much to do with the decay of the wood which is eventually an issue with any lumber product and cannot be avoided. The issue lies in the action between the house, the deck and the ground.
    Depending on the area which you live, and the type of soil you have, there is movement.
    Take for instance the area which I live, Kansas. We have a freeze/thaw cycle that is serious enough to cause upheaval at ground level. If our decks support columns were not secured to a footing, below frost level, the column would rise with the ground which would then translate that movement to the deck ledger board attached to the house. Do that repeatedly and you have recipe for disaster from the ledger bolts working away from the house rim joist.
    The 2006 IRC has some additional requirements for deck support column footings depending on the span of the deck joists, soil composition and frost line depth.
    Bottom line would be depending on the soil composition of your area, your freeze/thaw cycle, footing requirements and local jurisdiction. Here, footings are required to extend 36" below ground (our frost line requirement) for house footings, and deck footings.


  13. #13
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,248

    Default Re: deck post in contact with ground

    Quote Originally Posted by Michael Greenwalt View Post
    Take for instance the area which I live, Kansas. We have a freeze/thaw cycle that is serious enough to cause upheaval at ground level. If our decks support columns were not secured to a footing, below frost level, the column would rise with the ground which would then translate that movement to the deck ledger board attached to the house. Do that repeatedly and you have recipe for disaster from the ledger bolts working away from the house rim joist.
    The 2006 IRC has some additional requirements for deck support column footings depending on the span of the deck joists, soil composition and frost line depth.
    Bottom line would be depending on the soil composition of your area, your freeze/thaw cycle, footing requirements and local jurisdiction. Here, footings are required to extend 36" below ground (our frost line requirement) for house footings, and deck footings.
    The IRC states that, *IF* the deck is attached to the house in any way, shape or form, the foundations for the deck must be below frost depth just like those of the house it is attached to, HOWEVER ... *IF* the deck is a free standing deck and not attached to the house in any way, shape or form, then the deck does not require footings to be below frost level, the deck is free to rise and fall on it own, not being tied to the house in any way.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  14. #14
    mathew stouffer's Avatar
    mathew stouffer Guest

    Default Re: deck post in contact with ground

    except untreated wood may be used where entirely below groundwater level. I am confused, which is easy to do, but what does this mean


  15. #15
    Join Date
    Mar 2008
    Location
    Charlotte NC
    Posts
    2,303

    Default Re: deck post in contact with ground

    Quote Originally Posted by mathew stouffer View Post
    except untreated wood may be used where entirely below groundwater level. I am confused, which is easy to do, but what does this mean
    I believe bacteria need more oxygen than is in most water. I know that the stumps in the bottom of Lake Norman are very sound! I've tried to knock a few of them out with a lead keel and the stump never wiggled.


  16. #16
    Join Date
    Mar 2007
    Location
    Spring City/Surrounding Philadelphia area
    Posts
    3,473

    Default Re: deck post in contact with ground

    I saw this deck last week. Eight of the nine suport posts that were beneath grade level had varying degrees of rot and deterioration. The second pic here shows how much the deck was dropping at the outside edge.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  17. #17
    Join Date
    Oct 2003
    Location
    Rockwall Texas
    Posts
    4,519

    Default Re: deck post in contact with ground

    Nick

    Thats defeats all the talk that PT post don't decay now doesn't it?

    rick


  18. #18
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,248

    Default Re: deck post in contact with ground

    Quote Originally Posted by Rick Hurst View Post
    Thats defeats all the talk that PT post don't decay now doesn't it?
    Rick,

    All depends on what it is treated with and what it is treated for.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  19. #19
    Join Date
    Jun 2008
    Location
    Maryland
    Posts
    1,049

    Default Re: deck post in contact with ground

    6x6 from yesterday.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  20. #20
    daniel nantell's Avatar
    daniel nantell Guest

    Default Re: deck post in contact with ground

    Good find John , I guess they thought that putting rocks at top of 6x6 would prevent rot. If its in the ground its going to rot eventually and usually before the 20 years warranty expires.


  21. #21
    Join Date
    Aug 2007
    Location
    Memphis TN.
    Posts
    4,311

    Default Re: deck post in contact with ground

    Quote Originally Posted by John Dirks Jr View Post

    6x6 from yesterday.
    .
    Might want to consider leaving that Ring in the Truck.
    * could be a safety Issue ( climbing around & getting snagged on an exposed nail head. )
    .

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

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
  •