Just measured my 3/4" OSB new home subfloor for moisture content with my new Wagner 220 meter. Got readings from 8.5-11% depending on where on the floor the meter was. Even moving the meter an inch would change the % by a point some places. I have been running th A/C for 2 weeks and the rh has been 53% or so for most of that time.

I feel pretty comfortable with the content, but do I just average it out, say 9.5-10 or so and call it good? The 3/4" solid maple I'll be putting in is suppose to come in at 8-10%. If that is the case, no acclimation is needed, right? I will be starting the install in about 3 weeks, the wood is not ordered quite yet.

I would welcome opinions, thanks.

Well, the subfloor MC sounds good and if the maple is about the same +or- 2%, then subfloor content is fine. However, I'd still be checking that RH. It seems a little high to me with ac going. I'd think with ac, it should be closer to around 40 to 45% but perhaps you're in a real humid environment. If the RH doesn't change in the next week or so, then I guess that's as low as it'll go. In this case, I can't see anything to be gained by acclimating.

Thanks!
Yeah like I said the rh has bounced between 54-50% over the past 2 weeks. They primed the walls but have not painted or done tile yet so I will keep an eye on it. If rh jumps because of this, I will wait to put the floor in until it settles again.

So...should I see so much variation in OSB?

I sometimes see about a 2% difference using my moisture meter. Some areas will read 9% and others 11%. I was told one is to average the readings. Some readings 9%, other readings 11%= 10% average. Now, if those higher readings are all in one location and the lower readings are elsewhere, then that could mean there is a moisture issue where the higher readings are and some investigation needs to be done as to why.

The acclimation process can't even begin until all the "wet trades" have finished their work. That includes painting and mortar tile work. Then after a couple of days for the rH to stabilize, then bring the wood into those rooms, for acclimation.

Once again thanks for the replies!

Gary-
The higher readings are not just in one spot, they are somewhat random. (No lone wet spots with dry surrounding areas)

Floorguy-
I plan to install the floor about 1-2 weeks after tile and paint if all goes well. If rh spikes up I can buy a dehumidifier if needed I suppose. I know I'm starting out at 50-55% so I can monitor it from there.