I'm getting ready to install 3/4" x 3 1/4" Solid T&G Brazilian Cherry. I live in Indiana and run HVAC year round and maintain at 72-75 F. I'm currently ranging a RH of low 30%. I really need to get moving on a this project, and don't have the time to wait until mid-late spring for the RH to increase to 40% about the mid average for my area. I calculate out that the MC of the wood will at most fluctuate 6%, and that would equate to an expansion of 1/64". I found an article on line that mentioned "For low humidity jobsites that will eventually become humid, use one of the following methods to avoid problems, or make a note not to install the floor super-tight, leaving natural gaps alone.

· Use a .020" sheet metal spacer every 5 to 6 rows to leave small gaps
· Use a .010" spacer every 3 rows
· Use 'minute' spacers (.003") between each row. With Natural Reflections this can be accomplished by leaving the boards finger tight.

So my thought was to use a piece of paper or index card to put a small gap between each row for expansion.

What are everyone's thoughts on this or is there an easier way. Obviously I won't start the installation unless the flooring and sub-floor are withing the correct range and are the appropriate range between each. I'm just terrified of cupping or cracking.

Thanks

The paper might get stuck and tear, hence the use of metal spacers. Plus, drying down (acclimating) exotics is not a great idea.

Why isn't drying down exotics not a great idea? So would you use the 0.02" sheet metal spacer every 5 to 6 rows?

Because they tend to split and check at low rh. Why not get a stand alone humidifier or two? Exotics grow in jungles not in north America. What is the moisture content of the exotic right now outa the box? Whats the subfloor/underlayment moisture content? How close should they be before you install?

Right now the subfloor is around 5-6% and the wood is 5-6% but has been in the house for a week, that must have been around the MC the wood was Mfg at because its width is true at 3.25". The mfg recommends the wood and subfloor being within 4%.

Install away