My house is new construction and we are coming to the one year review. Our kitchen/dining room in 3/4 maple harwood flooring. The subfloor is OSB and then we have a 1/4 layer of what appears to be luan.

It seems that a few of the boards are loose.

Can any one comment on whether this sub-floor and underlayment would meet acceptable requirements? I am not a big fan of hardwood over osb and want to make sure that the builder did it right. If this underlayment is not acceptable what would be an appropriate solution to require of my builder.

(BTW, it was a spec house so I didn't have a say in the sub-floor.)

Thanks,

Nick

While neither of those products are GREAT ( OSB, luan ), IF installed properly, the hardwood floor should perform acceptably. If boards are loose, more than likely, it would be a problem with the installation than a problem with the materials used. I have installed different wood floors over that exact substrate and I have had NO problems.

Last i heard, not all OSB is considered acceptable for nailing solid. At the time, NWFA had a list of acceptable brands, it can even depend on the mill. You would need to see the stamp on the OSB. Call NWFA, my information could be outdated. An acceptable solution, if the osb is not up to par is difficult. Replacing the osb loses a lot of the structural integrity of the house. The walls rest on it. One solution might be to install a floating, engineered.
Loose boards can be caused by other reasons as well.

Hope this helps!
http://www.nwfa.org/member/pdf/Sect2.pdf

http://www.nofma.org/installation1.htm
"If plywood, 5/8" (19/32") or 3/4" (23/32") performance rated products are preferred Also, 3/4" (23/32") OSB is a comparable substrate"

Thanks for your replies. I appreciate your input.

Best wishes,

Nick