The installer advised you incorrectly. He doesn't know what he is talking about. There is supposed to be an expansion gap around the walls, but even if there were, the floor would still buckle. The maple will expand and contract with the climate change, but the plywood will not. Thats why the floor buckled. If you want to know the correct way to install a hardwood floor over cement, go to a home center and get a book that tells you the correct way, or google your question. You should have used a floating floor made of engineered wood.
Take your guy to small claims court. He doesn't know what he is doing.

You need to send him a registered letter requesting him to fix your floor so you will have a written record that you in fact asked him to fix his job or refund your money.

If you are in NYC and the contractor is licensed by the Department of Consumer Affairs as a home improvement contractor, then you may get some assistance from DCA.

Poured concrete gives off moisture for a very long time, and slapping some plywood on it was no solution. He wants you to acclimate them for a year AFTER they've been installed? The guy is a crook IMHO.

Are you below grade?

Is the floor on grade?

Second floor?

Gluing and nailing is NOT going to stop wood movement from changes in moisture content.

Is the flooring 'engineered' with cross ply construction or solid wood?

"We have never installed a plywood system for hardwood if on grade..."

You have never installed a 3/4 inch hardwood strip floor on concrete?

You need wood to fasten the floor.

Thank you so much, everyone, for all your comments so far! I was supposed to receive emails for follow-up posts so I apologize for the delay.

It's amazing but while shopping for my hardwood floors, I visited several floor stores and only one had mentioned that installing hardwood floors over plywood in a hi-rise condo is not the best approach to installing hardwood floors but in fact engineered wood is the way to go.

Someone2010: Thanks so much for your advise but could you clarify? I would be willing to send him a registered letter and take him to small claims court but what exactly would he be fixing? Would he come back to create an expansion gap (even though the expansion gap wouldn't resolve the buckling issue), refund the cost of installation, or refund the cost of installation and the material so I can replace it with engineered floors (and through another installer of course)?

idrive65: I could get into other things that he has said and done to me but he clearly does not know how to respect women.

Brickeye: I'm not sure if I understand what you mean. Could you explain what "grade" you're referring to?

Since my first post, my floor guy has tried to counterattack by threatening to send a list of extraneous costs. If I have already completed payment with him, does he have any right to send me an extra bill? I have already requested his extra bill and will now start the process of documenting the case for court. I have a long battle ahead of me.

I would like to complete this project before the year ends so I have a new contractor that has suggested removing the boards that run parallel to the wall and reinstalling pieces that allow for the 3/4" expansion gap. On the boards that run perpendicular to the wall, he has suggested cutting them to create the gap. Since small claims court will delay this project considerably, is it wise to have my current contractor fix the problems now and try to bill my floor guy later? We need to move in soon.

Thanks again for all the input and suggestions!

Thanks so much again for all the feedback.

"Could you explain what "grade" you're referring to? "

Grade is the earth level around the house.

Sorry to hear you are having problems with your hardwood floor. I have Mirage maple floors in my house. I have had no problems, but they were not installed over concrete.

You have a installation problem. It is the responsibility of the installer (store provided or independent) to install the floor correctly. The installer has to do whatever it takes to correct the problem.

So far he has given you lame excuses. Floor don't buckle because the weather is changing. It does not take a year for a floor to acclimate to your home.

What extraneous charges is the installer giving you? Is he the installer supplied by the store?

I fear adding expansion joints may not solve the problem. It sounds the installation was not properly and may have to be redone. I hope this is not true, but be aware this may happen.

Being inexperienced or making installation mistakes does not justify calling someone a crook...IMHO.

The floor installed on summer when the humid very hgh?

Here is a link that might be useful: Hardwood Flooring NYC