I have experienced some small basement flooding in my 1.5 year old home. The sump pump has been working continuously and with all the rain here in the midwest it would go off every 3 to 4 seconds. Now it is going on every 10 to 15 seconds as the rains have stopped.

A few days ago we had small puddles in the low spots in the middle of the floor by some seams. This was weird as it was not by the sump pump or near the wall or corners. I dried this up with towels, fan, and a dehumidifier. The builder said that there is too much "pressure" and that the sump pump could not keep up and that the moisture cam up from the ground through the seams.

Does his explanation sound accurate? Is the builder responsible for fixing this? What can I do about this to prevent future problems when I end up finishing my basement?

Any help / suggestion is appreciated.

Thank you,

Will

Make sure that you have a submersible sump pump as they are more reliable then a column pump and can pump out more water faster. Also shut off your sump pump and see where the water level stops. If it does not come over the top of the pit then set your pump float to come on at this level. Due to the ground water levels you may always have water in the pit and if your pump is set to low you could be trying to pump out the entire subdivision. You should not have "seams" in your concrete floor and under no circumstances should you have water coming through the concrete. Get on your builder about this. If necessary, get another foundation expert to come and look at the problem.

Builders have a habit of creating a corporation for a sub-division and then dissolving the corporation when division is complete. When that happens there is no one to make good because the "builder" went out of business.

Yes it is possible by hydrostatic pressure to penetrate concrete. There are coatings to prevent this.

Another possibility is "dew point" which is similar to the concept of frost. Builder would not likely be responsible for this. A table exists that would list the temperature and humidty of the surrounding air and the maximum surface temperature in which water would condense.
Once it becomes conditioned space, the problem will generally go away. De-humidification also helps.

A simple sump pump in the floor may or may not work. An elaborate french drain system may be required as well as foundation work to prevent flooding.

A drain in the floor might overflow which could be another cause.

Did the contrator put a vapor (plastic) barrier down before pouring the concrete? Did you have a French Drain installed around the perimeter of the basement? In the state of TN the contractor is liable for one year after the completion of the building. I do not know where you are located but you may be able to contact your state's licensing board to help get this resolved and to find out the limitations of liability in your state. Did you contact the contractor before the end of one year, or whatever the statue of limitations is in your state, or locality? If so, he or they may still be liable. Contact your state's Dept. Of Commerce and Insurance. At least that is whom you get your contractor's license from in the state of TN. Please let me know how this turns out.