Gary,
The screeds in this gym are treated and they were embedded in mastic with no fasteners. Hot tar was poured on the concrete between the 1x4 screeds to about ½” deep. We replaced a few loose or broken screeds and used treated.

And Gary,
Write the book. Your knowledge, attention to detail and communication skills will make a great book.

Chuck,
The screeds are black because they are saturated with black oil from the mastic and the tar. They have also been underwater a few times.
When these older gym’s were built each architect (if the job had an architect) had his own idea of how the floor should be installed so we see many different methods.

Buddy

Did you by chance check the MC of those treated screeds?

Treated wood is known to have a high MC.

Floorguy,
We always have a good supply of treated 1x4's and 2x4's for screeds. We use them mostly for repairs. We stand them up along the walls of our warehouse and air dry them.
And yes, we do check the MC.

Buddy

Look at

Great explanation, Chuck.

LOL, That's why I asked if he pinned the screeds! His eyeballs would have popped out

Chuck, are his fasteners going to puncture the moisture retarder?
What, maybe 5 to 6 times, or more in a sq.ft. space??

Puncturing a vapor