What the deal?!

The 3/4" solid 2-1/4" pre-fin braz walnut has been in the house for 3 weeks now (June in San Diego) and a Tramex meter shows from 10 - 15 percent on the wood moisture content scale. Checking the 90-yr-old 3/8" white oak flooring in the rest of the house -- wood joists over dry dirt crawl space -- shows similar (10 to 15), without cupping. From what I've read, this is rather high MC for the flooring.

Checking weather.com our humidity has been 50-75 with temps 65-75. No A/C (windows and doors always open--it's San Diego).

So it looks like the new flooring has acclimated, but to a kinda high MC. Should I wait till October? Should I install now--at it's "fattest"?

Why hasn't the old oak suffered after 90 years?

-Brad

Sounds like the flooring is ready to go. Density of the board will effect the MC readings, with an electronic meter. I poke other wood in the home, and it will tell me what the wood will read when it comes to equilibrium.

I'd say the interior of your home is around 73-75º and the humidity is around 58-60%

I'm trying to figure out why you are getting a 50% jump in readings... 10-15 is a little strange. Bottom line is the new strip flooring needs to be within 4% of your existing substrate. Sounds to me like you are there.