Here are the facts regarding some flooring I am waiting to install to help complete the remodel of our main living area:

- Louisville, KY area
- HVAC is working and has been working for 6+ months at this point
- Relative humidity in the house is 36 on one side and 40 on another. During the warmer months, I've seen it around 55 and sometimes almost 60.
- We are running a wood stove in the basement on the drier side of the house and the temp is around 75°. Other side of the house is heat pump based and stays at 70°.
- I'm using a push in moisture meter I bought on Amazon for < $20
- We have 70+ boxes of Bellacera engineered hardwood (4", 5", and 6" planks) and we've had it for a couple weeks at this point.
- They are stored on the main level in various rooms. Currently, they are all stacked in various piles and most of the boxes are not open. I opened a few to let them breathe.
- We will be using nail + glue assist
- I plan to use a roll-on moisture barrier over parts of the house that are on a crawlspace even though the crawlspace is conditioned.
- Its an open concept house and there are areas of flooring that will be 40' long x 40 wide...so potentially a lot of movement even putting a 1/2 gap on the edges (which is about the most I can do unless I bump up the wide of my base trim).

Regarding moisture, the Bellacera install instructions (https://www.bellacerafloors.com/hardwood-floor/installation.aspx) say:



Moisture content readings:

- 18% - taken from newly open box
- 16% - taken from box on drier side of house that has been open a couple weeks
- 13% - taken from box on other side of house, also open a couple weeks
- 10% - taken from "demo" pieces that we bought earlier and have been out of the box for 6+ weeks. That piece has been on top of the stack and has measured the same for a couple weeks.
- 0-2% - subfloor moisture

Based on the above, it seems like 10% is likely the lowest moisture content the wood is going to reach in our home? That doesn't make sense to me based on what I've seen in the temp/RH charts online. They seem to say 70° and 40RH should be 7-8% wood moisture content and at 60RH it should be around 11%.

I have four questions:

- Should I buy a more expensive moisture meter? I got this one for firewood years ago but we are talking about $12K worth of flooring now. If so, recommendation on brand or model?
- What do I do about the subfloor being way drier than the flooring? Does the difference called for in the install instructions only apply if the subfloor is wetter than the flooring? Would putting roll-on moisture barrier everywhere help?
- Since I'm on the low end of the RH range we will see annually, would it be better to install the flooring with a bit more moisture in it vs waiting for it to all get down to 10%?
- I'm intending to use 1-1/4 in. x 18-Gauge cleats. I understand from the sticky thread in this forum that staples may hold better but you might actually want to permit a bit more movement in which case cleats are better. Should I reconsider?

With solid wood flooring the moisture content of the flooring should be within 2% of the sub-floor. What is the reading of the sub-floor? Compare this moisture reading with the flooring.If you are using glue assist the cleats are just holding the flooring until the glue sets up. I think that you do not need more than a quarter inch at the edges, even with a wide area since the flooring is engineered.

Pete, thanks for responding.

Per my post above, the subfloor is reading 0-2% moisture depending on where I take the reading. The instructions given by the manufacturer, which I linked to above, say the difference between subfloor and flooring should be no more than 4%. But given that flooring that's been in the house unboxed for six weeks still reads 10%, I don't have any idea how I'm supposed to get it down to 4%. That also seems kind of wrong to me. Won't the flooring be too dry at that point?

A zero or small moisture reading can not be possible. I think 10% for the flooring will be fine for 30-60% relative humidity in the future.