Straight answers
The things people ask on the phone, answered the way we answer them on the phone.
Usually not, but not always, and the difference is worth establishing. Concrete shrinks as it cures, and fine cracking that appeared in a home's first year and hasn't changed since is very common.
What raises concern is a crack that's wider at one end, one that runs diagonally from a window or door corner, one where the two sides sit at different heights, or one that has visibly changed recently.
For a stable hairline crack, sealing it to keep water and insects out is reasonable and there's nothing wrong with doing it yourself.
The risk is sealing a crack that's still moving. It hides the evidence without fixing anything, and the same crack reopens once the ground shifts again. If you aren't sure whether it's moving, find that out first.
Mark each end with a pencil line and write the date next to it. Take a photo with something for scale. Look again after a wet season and a dry one.
This costs nothing and it answers the single most important question about any crack. It's the first thing we suggest to people who call and aren't in any distress about it.
Sandy soil and a lot of water. Sand supports concrete well when it stays put, but water running through it in volume carries it away, and that leaves voids under a slab.
On top of that, soil swells in the rainy months and shrinks in the dry ones, which works a foundation back and forth every year.
Yes, and it's one of the more common causes we find. A supply line under a slab leaks continuously and washes soil out from under the concrete for months before anyone notices.
Warm spots on the floor, the sound of water with everything turned off, and an unexplained rise in the water bill are the usual clues.
It's the single most under-rated factor. A downspout emptying against a corner of the house concentrates a very large volume of water at one point.
Extending a downspout and fixing the grade is cheap. A meaningful share of foundation problems here started as a drainage problem nobody dealt with.
For significant structural movement, yes. An engineer is retained by you, has no financial stake in which repair gets sold, and can specify what's actually required.
We would rather point you to one than quote around a question that should be answered properly.
Yes, on anything substantial. Foundation repair is a field where the difference between quotes can be very large, and where work is sometimes sold to people who didn't need it.
If a quote is presented as urgent and only valid today, that alone is worth being sceptical about.
Often not. Stopping further movement and returning a foundation to its original elevation are two different goals.
A slab that settled years ago and has been stable since is frequently better stabilised than lifted, because lifting stresses plumbing, tile, and drywall that have long since adapted.
In Florida, licences can be verified with the Department of Business and Professional Regulation. Ask for the licence number and check it, and ask for proof of insurance.
Do this for anybody you're considering. It's normal and no legitimate contractor is offended by it.
Call and ask it. Most get answered in a couple of minutes without anybody coming out.