Solid Hardwood, Engineered and Laminate Flooring - Laying flooring in humid weather

I have slowly been replacing the carpet in my living room with Bruce hardwood oak strip flooring (as the budget allows.) I am on the home stretch and would like to finish, but I'm concerned about putting the flooring down while we are experiencing this hot, humid Northeast summer weather. My fear is that when the weather dries out the flooring will shrink and gaps will appear. Is this something I need to be concerned about?

Thanks - The Old Tory

YES! search this forum for "moisture meter" and you'll pull up many threads discussing this subject.

Here's (http://forum.doityourself.com/showthread.php?t=262906&highlight=moisture+meter) one for starters.

As long as temperature and humidity are within occupancy levels indoors and HVAC is running and doors and windows shut you should be fine. (Humidity level 35-55% and temperature around 70 degrees). If installing over a crawl space it should be dry and well-ventilated and 8# minimum polypropylene vapor retarder installed over soil, overlapped, taped, and run up inside of foundation walls and taped. If installing over a basement, there should be no moisture or humidity issues.

A moisture test should be taken with moisture meter of subfloor and hardwood flooring that has been sitting in rooms where it is to be installed in order to acclimate to temperature and humidity of rooms. For solid 3/4" x 2 1/4" hardwood there should be no greater than 4% difference in moisture content between wood and subfloor. For plank, there should be no greater than 2%. Continue to acclimate if moisture content is not within range.

A 15# minimum roofing felt vapor retarder is installed over subfloor (3/4" plywood or OSB), overlapped, and stapled. A 3/4" expansion gap is left around perimeter of room to accommodate expansion. Wood tends to expand and contract as temperature and humidity fluctuates inside the home. Maintain temperature year round at around 70 degrees and humidity between 35-55% (measure with hygrometer sold where they sell thermometers).

I'd be more concerned installing it during the winter and everything is dried out and shrunk from the heater running. Then summer time and humidity and you have to tear out the flooring because you have mountains of buckled wood flooring.

A 15# minimum roofing felt vapor retarder is installed over subfloor (3/4" plywood or OSB), overlapped, and stapled.

I've always wondered about this -- wouldn't the overlap be pretty thick being 2x15# felt thickness at the seams? or are you supposed to run the wood perpendicular to the felt?

Thanks!

-Graeme