I've got a project with 5.5 inch thick elevated concrete slabs on 2 inch composite metal deck. To what depth do the humidity probes get installed? 40% of 5.5 inches? 40% of 3.5 inches? By the time the flooring gets installed the building is essentially finished with ceiling components and makes it difficult to determine the high and lows of the poured concrete deck.
Check the Wagner YouTube. They just posted a video on that I think.
Thanks! I just watched the video. What is the recommended model of "metal detector" by Wagner? Any other quick and simple techniques to avoid the interference from the reinforcing steel (rebar, WWF) that is in the concrete?
I guess the answer right now is 40% of the deepest part of the elevated slab. How does installing the probe at 40% of the shallow thickness effect the reading?
I know it sounds crazy but this is a good tool to have just to check to see if a slab does have continual steel reinforcement.
You can also see where the rebar is so you don't hit it.
I used one to scan 6" on center rebar when I was taking 4" diameter cores. It works great!
Concrete Answers for Flooring Problems
03-23-2011, 05:12 PM
(This post was last modified: 03-23-2011, 05:34 PM by mwoody.)
We utimately used the old rule of thumb the CC mentioned for the probe depth, but does that meet the intent of the ASTM and Wagner for acceptabitily?
I found this in the do's and don't thread:
"When measuring concrete poured in a fluted pan, take the thickness of the concrete above the flutes (i.e. 4") and add 1/2 of the depth of the flutes (2" fluted pan means you would add 1" to the 4" for a total of 5") and drill your hole 40% of that measurement. I have not seen official documentation on this issue released yet, so please check beforehand. I believe the new ASTM will address this."