I'm having a house built and they just completed pouring the slab for the foundation a few days ago. When I inspected it today I noticed several narrow (but sometimes long; one or two do them appear to run nearly across the entire slab) cracks in the concrete. Here are some pictures:
Can anyone tell me if this is something I should be concerned about, or is it standard to find these kinds of small cracks in freshly laid concrete?
Secondary question; I also noticed a few other things that seemed like defects. Are any of these cause for concern:
Missing chunks of concrete:
Fastener not secured to anything:
Footprints in shower recess concrete:
Edit – Here's a shot of what was in place immediately before the slab went down:
Best Answer
Concrete will crack naturally on its own unless it is given a place to crack such as control joint or expansion joint. As the concrete is curing it is heating up and expanding. In the summer time, I have seen the slab crack before being able to walk on it.
Regarding footprints, it is tacky. However, the roughness can actually help the concrete and thinset to bind unless it is flaking.
One criticism......the young lady wearing the flip flops should not be walking around a construction site. Stepping on nails, rusty re-bar, broken glass etc is a distinct possibility. Safety first!
As suggested by another responder, if you feel excessive water has been used then a core sample can be done and a test break can ascertain whether the concrete is no good.