Have lived in Florida for over 30 years and have had lots of cracks over the years in our homes due to shift in soil here and no basements.. My husband is a native and he says this is common, you can always ask home warranty department to get another opinion for you.. I have been here since April and we do not hesitate contacing them for anything we think needs to be addressed.

Concrete will crack. The real question "is the crack minor or major"? How is the difference defined in your contract? I would consider hairline cracks normal and minor. Any crack 1/4 inch wide would be major. Maybe even 1/8 inch wide would be a concern.

There is a product made by Rust-Oleum to repair concrete cracks. It is a two part epoxy mix. I did the epoxy paint in my garage in VA and repaired many cracks prior to painting. I mixed the epoxy and using a putty knife to put it in all the cracks. And I had many as the house is 30 years old. You let the epoxy dry 24 hours and then sand smooth. I had so many I rented a floor sander from Home Depot. Then painted the floor with the epoxy paint after cleaning and etching. You cannot find the cracks now. Even knowing where they were, I can't find them. I had one so bad I used a sledge hammer to break out the concrete and patch with concrete patch and then make smooth with the epoxy and you can't see it.

As long as the concrete was installed properly with rebar and 5 inch wire screen, minor cracks are not an issue and can be fixed before painting so you will never see them again.

Except for a few rods at the perimeter, there is no steel in the house slabs here. They use fibercrete, which has fiber mixed in with the concrete. That being said, i take exception to the notion that all slabs crack. If the control joints are placed properly, and the concrete is allowed to cure properly, and the soil underneath is compacted properly, they will not crack. I have never seen anyone do a compaction test here. I was involved with quite a few homes in Collier county, and we did a wet cure, that is, we ran the sprinklers on the slab for 3 days after pouring. Result: NO CRACKS

It is my understanding that construction on the slab should not be done within a week of the pouring. I have seen several houses where the concretre was poured one day and the crews are on site the following day erexcting walls. I just wonder if they use something to cause the concrete to cure over night.

One way to check for voids under concrete slabs is to simply drop a golf ball from chest high and listen to the sound as it hits the floor. A click is good ...a hollow sound is a concern.

Concrete cannot cure overnight. No matter what you do to it, it takes 28 days to fully cure.

:undecided:When I questioned the cracks on my lanai floor they sent out the foreman from T & D and he told me cracks are normal. He also said if I would pull up the carpet I would find more cracks. I asked him if he had ever been to Italy where they have been using cement for over 2K years. Some of these buildings have no cracks even in areas subject to earthquakes. I feel that they pour fast and build quick here, I for one am not convinced that concrete and cement will crack. With no Rebar it will crack.:spoken:

rebar has little to do with cracking

I was told by an inspector if you can fit a quarter into the crack then you have a problem. Anything smaller is considered normal.

It may be common, but it is not normal. If curing is correct, compaction is correct, and placement is correct, it does not have to crack. I could show you 30 year old slabs with no cracks.

A contributing factor may be that the concrete isn't allowed to "cure". I've been watching all the new construction going on around me for the last 7 months...concrete is poured, and building on the slad begins no more than 3 days later, weather permitting. Strangely, when a patch of concrete had to be repaired on my driveway, we were told that the patch would have to "cure" for a minimum of 30 days before re-painting to match the rest of the driveway. Go figure...

See above posts

I've been a Mason for over 40 years,

Mulligan is mostly right !

Yes, Shimpy is correct about step cracks in block homes (they appear in the shape of steps). It is important to check your exterior periodically for such cracks in both hot weather and cooler weather as they may appear one day and not the next due to expansion and contraction.
In our former neighborhood near Tampa, my neighbor across the street had step cracks down his side wall and his neighbors sprinklers were hitting the side of his house which had the step cracks and allowing moisture throught the block. Eventually, that side of his home had a ton of mold between the walls which needed to be gutted. Driving rain can also have the same effect.
We live in St. James, our home less than a year, and have already had one repaired. Just keep an eye out, preventive maintenance.

You may not like it,,,you may not believe it,,,but this is true