Ya, he got "hop'n mad"

You have caught him cutting corners.

a 5" wide board, can swell considerably, with just a 3% gain in moisture content. 2" in 10 feet(or 20 rows)


This sounds(won't know for sure, without being there myself) like a total installation related failure.

Thank you all for your responses!
-I will have my husband check his measurements for sq. ft.
-It is a re-model of a barn that my parents were living in 1/4 for 20+ years. The remaining was re-modeled with the woodflooring in question in the great room. The concrete was there before they purchased in 1975.
-The contractor said he put a meter on the boards and the reading was good.
-He did not get a meter reading on the concrete, he said he could tell by laying his hand on it that there was no moisture problem. He did not seal the concrete in any way. The only moisture barrier he said he used was the black roofing paper.
-The buckling was not over the entire floor. I would say about 1/3 of the room had some, ranging from slight to severe. The most severe (raised about 3") he had left no expansion room. He came back and fixed that.
-The plywood was down for probably a couple of months. The home was closed up when flooring was brought in to acclimate.
The contractor is asking my mother what she wants him to do. She has no idea what to tell him. She is holding his last check, which makes him very unhappy (the flooring is not the only issue). He got hoppin' mad when I questioned him about expansion space, moisture content, moisture barrier, ect. (all information I gained from your site).
I guess he should first go back and cut the proper expansion space.
A couple ideas that have been suggested are 1)to branch off of the ductwork under the floor so there is heat & ac blowing underneath, 2)to cut 2" vents in the floor to allow movement of air. Are either of these good attempts to try to alleviate moisture that may be trapped under the floor?
Again, thank you for your guidance. You have provided us with a source if information when we didn't know where to turn. Terri