Is this concrete or gypcrete?

Discussion in 'General Flooring Discussion' started by Douglas Fir, Jul 25, 2019.

Help Support Flooring Forum by donating:

Tags:
  1. Jul 25, 2019 #1

    Douglas Fir

    Douglas Fir

    Douglas Fir

    Member

    Joined:
    Jul 17, 2019
    Messages:
    5
    Likes Received:
    0
    Location:
    California
  2. Jul 25, 2019 #2

    Floorist

    Floorist

    Floorist

    Administrator Staff Member Admin Moderator Pro

    Joined:
    Feb 21, 2011
    Messages:
    11,382
    Likes Received:
    4,070
    Location:
    , Missouri
    Take a screwdriver and dig in. If you can dig into it easily, it is gypcrete. It is much softer than concrete.
     
  3. Jul 26, 2019 #3

    Douglas Fir

    Douglas Fir

    Douglas Fir

    Member

    Joined:
    Jul 17, 2019
    Messages:
    5
    Likes Received:
    0
    Location:
    California
    Ok, in that case it’s definitely concrete. The abrasion mark on the top half was from a sledgehammer. Thanks!
     
  4. Jul 26, 2019 #4

    Floorist

    Floorist

    Floorist

    Administrator Staff Member Admin Moderator Pro

    Joined:
    Feb 21, 2011
    Messages:
    11,382
    Likes Received:
    4,070
    Location:
    , Missouri
    You can easily drive a nail into gypcrete. Concrete is tougher.
     
  5. Jul 27, 2019 #5

    Ernesto

    Ernesto

    Ernesto

    Professional Pro

    Joined:
    Jun 25, 2011
    Messages:
    6,174
    Likes Received:
    1,332
    Location:
    , AZ
    One test is the scratch test. If you can dig a nail into it rather easily its gyp.
    I've seen gyp poured over top of concrete for a floating floor system. Mostly its overtop of plywood. No one does real concrete over a wood substrate. Lightweight concrete is different than gyp as lightweight concrete is poured overtop of a metal pan.
     
  6. Jul 28, 2019 #6

    highup

    highup

    highup

    Professional Pro

    Joined:
    Mar 6, 2011
    Messages:
    9,029
    Likes Received:
    2,044
    Location:
    ,
    The image is very confusing. Too close up, and it looks like a beach with driftwood or some rotten wood laying there.
    Gypcrete can be relatively hard on it's surface if it's poured correctly and has the sealer on it. That said it's soft once you get past the top surface.
    Soft is a relative term.
    The photo again shows no scale to determine what we are looking at. Looks like there is an 18 inch piece of rotted wood in the photo............... but nobody uses wood chunks as a filler in concrete or Gypcrete. Gypcrete has fine aggregate and the image shows what looks to be large aggregate. Even light weight, pumped in concrete would probably have smaller aggregate that what's shown.
    Like I said, the photo is very confusing.............. looks like another planet because it includes no visual references as to the size of what we are looking at. Another photo or two would help a lot.
     
    Last edited: Jul 28, 2019
  7. Jul 28, 2019 #7

    Floorist

    Floorist

    Floorist

    Administrator Staff Member Admin Moderator Pro

    Joined:
    Feb 21, 2011
    Messages:
    11,382
    Likes Received:
    4,070
    Location:
    , Missouri
    Be aware, if it is gypcrete, it may be less than 2 inches thick and poured over 3/4 " plywood. I see that all the time. I have never seen a concrete floor like that because of the weight.
    If you have ever wondered why gypcrete is not used in basements, it deteriorates if it comes in contact with dirt. My uncle worked in a place that made gypcrete blocks. Customers were warned that they were not to be used for foundations.
     

Share This Page