Concrete thickness???

[67 455 Bird ragtop]

Can you tell a difference between 6" thickness and 4" thickness by taping with a hammer??

The reason I ask is when I built my garage I had the concrete guy pour a little extra where I wanted to put my lift. I based it on teh length of our F-150. After he poured it he couldn't find the drawing I gave him since this was a last minute change that wasn't part of the original plans. And now I can't remember exactly where I had him put it. I have a pretty good idea but....

Any suggestions besides drilling a few test holes???

 

[t. jones]

Obviously don't have in floor heating if you want to drill test holes. You can test for voids under concrete easily by bouncing a steel bar.
Thanx Trevor

 

[raildawg]

ultrasonic tester.we use to use one to test the wall thickness in evaperator well(metal skin)thickness.dont know if it would work but might be worth checking on.good luck.

 

[Possum]

What does the lift manufacturer spec out for concrete? In a lot of cases 4" is enough so you might not have to worry about it.

 

[67 455 Bird ragtop]

They say 4" is fine. I just wanted to be a little safe. Especially since it wasn't all that much more for that small area.

 

[brownbagg]

i would drill a small hole and stick a piece of wire in it, it can be as little as 1/8 inch

 

[HemiMan]

Tapping will only tell if you have delaminations or a void. Best bet would be to drill a small hole.

 

[67 455 Bird ragtop]

i would drill a small hole and stick a piece of wire in it, it can be as little as 1/8 inch

This is my backup plan. My concrete guy is looking through his records again to see if he can find the drawing I gave him.

 

[67 455 Bird ragtop]

Another thought. I know he put rebar in the "hole" he dug for the extra thickness. Would a metal detctor be able to locate the rebar through the concrete ??

 

[OccupantRJ]

I would try the metal detector before I went to drilling holes, because it's non-invasive.

RJ

 

[t. jones]

maybe, I used just a cheap stud finder but I knew where to look.