Hope this message is not too late John. After much hassle with the builder our sloping upstairs floor has been traced by Engineers to the Post Tension Foundation where we have located one tendon that was never stressed and broke when they attempted to stress it after 5 years. Our Engineer has found through core samples that there is one tendon too deep and cannot find any more tendons or re-bar throughout the house, so we assume that the others are too deep also. We are finding that apparently there was no engineered site preparation plan, and no pre or post concrete pour inspections, and no County inspections that the builder assured us in writing had been done. The Builder wanted to fix the upstairs with cement latex float, that had been attempted by the builder before we purchased this newly constructed home. Our Engineers have labeled our foundation as: "Extremely non uniform, economically uncorrectible, below industry standard, no known way to repair." We are in litigation and hope that our jury trial will be this year. Should you have any questions I will surely try to answer them. Good luck to you