I am having a new home built on Cape Cod. The day they poured the concrete floor a storm was predicted and it rained and snowed that night. The floors are a mess, pitted, uneven etc. The builder finally looked at them after the house is framed and enclosed and said they were not acceptable and they would have them fixed but probably not for several months. I am enclosing pictures (the best I could do). I am very concerned that they might do some quick fix that will not last more than a couple of years. I don't know how I should proceed.! Should I get an engineer to look at them? Ever since there has been standing water in the basement and I'm not sure what harm that has done. basement floor after storm

basement floor

basement floor with snow![][3]

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    A self leveling compound will likely be their solution, and on new concrete, it shouldn't have difficulty getting a good binding. My own fear is that excess water in curing concrete can weaken the chemical reaction that's occurring, so this concrete may not have the expected strength. You can have it tested and compared to your local codes, but this late in the process I don't know of any easy fix (there's a reason they pour foundations first and not last). (Only posting as a comment because I'm not an expert.) – BMitch Mar 24 '14 at 13:07
  • I have some opinions about this but I think I would need to know how the soil was prepared, what type of binding technique (rebar? how much?), how thick the concrete is, and then I would ask you to take a chisel or screwdriver to this - does concrete pop off easily if you strike it at an angle? Also what were the temps like when walls were poured and a week before and after floor was poured? – DMoore Mar 24 '14 at 16:16
  • I don't have the answers to your questions, but the temp the day before the floor was poured was below 32 degrees and we were told that they had to pull out of pouring because they found the ground was still frozen, so they poured the next day with another snow storm predicted. The temps have basically been at 32 degrees or below since the footings were first poured. There are no rebars in the floor just sand and I have no idea how thick the concrete is. – Linda Cape Cod Mar 24 '14 at 18:51

If it would ease your mind, hire an engineer to look into it. Of course, having built a house on top of it, it's a bit late to do over.

However - if this is a typical New England house, the floor (that looks horrible, yes) is not holding up your house. The footings and foundation walls, which are normally poured before the basement floor, are the support structure. The basement floor is just a floor.

Water and concrete have an interesting relationship. Excess water in the mix does make the concrete weaker. Once the initial set has taken place, there is no such thing as too much water - one method for making high quality concrete runways is to flood them for a month after they are poured. Wet-curing concrete makes it stronger.

In your case, I suspect what you have is a little bit excess water on the surface before the initial set was complete, and a lot of letting the concrete freeze before it's cured. The surface damage is called "spalling" if you want to look it up. That does not say very nice things about your general contractor or your concrete sub-contractor, in my opinion - they should either choose to work in a weather window, or be prepared to protect and heat the concrete for a proper cure if working in the winter. The document linked above from the Portland Cement association specifies that fresh concrete should be maintained at or above 50F until it is cured (and curing takes longer at that temperature than the "standard" 73F.) Unless you are planning to put a machine shop in your basement (a good thing to have, IMHO) a self-levelling top surface will probably be adequate for most normal household uses. But you almost certainly don't have the floor you should have.

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    Excellent answer. Pouring concrete in freezing temps or bad weather is always risky and the addition of calcium to make it set faster can weaken the mix. The fix in this case will never be as good as a properly poured and floated floor. It will not be monolithic and at risk for surface failure. – shirlock homes Mar 24 '14 at 21:57

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