I’m pouring a small slab for some pool equipment. It will be 4’x8’x3.5”. I expect little to no foot traffic, just a heater, pump, and chlorinator. (Mabye foot traffic just when adding tablets)
Do I need a control joint in the middle? Or do you think my slab is small enough to get away with nothing.
(I have minimal concrete experience in slabs… just things like post holes and filling blocks)
Best Answer
No. My rule of thumb (can't recall where my thumb got it from) is 12 feet/4meters before you really need a control joint.
Reinforcement is always a good idea.
This document has a great deal of vague handwaving, and on page 11 gets to a specific recommendation from the ACI of "24-36 times slab thickness" which in your case is 7-10.5 feet. that suggests that 0 or 1 control joint might be the right number (with the 1 making two 4 foot squares per another recommendation found in the same section of the document that the slab segments defined by joints be square or near square.)