You Make the Call!
There are two basic causes of cracks in concrete. One is stress due to applied loads and; the other is stress due to drying shrinkage or temperature changes in restrained conditions.
Now look at Photo 4a. Do you see what I see? That’s right; the crack in the floor runs up the block wall! This is a site-related condition that is due to major movement in the slab; usually these cracks are not straight, and are very random. They are not foreseen or engineered by the architect. This, of course, is not installation related, and the general contractor and his concrete people should look at this condition. What about Photos 3b and 4b? Do you see how the crack forks around the steel (vertical) support? This is a great example of an isolation joint that has done its job. Can the installer be held responsible for this? This too is a site-related condition; no patch and adhesive combination will keep this from happening. Now look at Photo 5b; this will give you some indication as to the amount of movement at this crack. The repair will be to ramp the patch up to the higher edge and feather it out to the lower field.
This is a type of repair, involving labor and material costs, which the building owner will have to pay for.
It is no secret that the floorcovering industry and the concrete industry at times seem to be miles apart on several schools of thought. But, we must understand who knows best about their particular area of expertise and listen and learn from them. It is customary in our industry to use a fortified Portland cement patching compound to level out subfloor irregularities in concrete when a resilient floorcovering is to be installed.