bamboo(carbonized) hardwood over concret subfloor. I live(in Denver) on the 5th floor in a mid-rise. Install finished Dec 31, 2005. Soon after I had one area that "popped". He came out and drilled and filled with epoxy. One week later the two boards next to it popped. He drilled second hole and filled with epoxy. Within two weeks the next boards were popping and the inital boards crackling. I noticed this crackling in other areas. As time goes on.... more crackling and other areas popping. I have also noticed a lot of lumps and bumps in the floors. Like a roller coster. Is this "cupping" . What is cupping? Also, he put base all around. It didn't hit the floor in a lot of areas. He then caulked it. Now the caulks is pulling away and the base looks like it is floating. I paid a lot of money for this floor. 600sq. He charged me 4.50/sq foot plus the cost of glue for 900/sq. ( plus base etc...)I was under the impression he needed the extra glue to level?? I am sick, sick, sick. He can't understand why it would be getting worse over time, but it is. I think it was the install. The lumps and bumps are becoming more and more. PLEASE any info will help. Dianna[/b]

I do not think it is cupping from moisture since you are on the 5th floor of a building; unless the windows or walls are leaking but that is highly improbable. Perhaps you have light weight concrete (often called gypecrete) that was spread over your subfloors. This is common in high rise multistory buildings. But I am not very experienced with these type of installs. I do know one is not supposed to glue to them without some sort of treatment to stiffen the surface. Or you need to have a floating type floor. Perhaps Perry or Ken will be able to answer your question better.

1st floor, 5th floor or the 100th floor, if it has a mix of water and concrete, or gypcrete, it has moisture vapor emissions. How high or low they are we don't know.