I've learned much on this forum! Thanks again to all those here who are so willing to share with others.

My 3/4" Prefinished Bruce Hardwood (CR3455) is now acclimating in the room it will be installed in for the next phase of my project. I have borrowed a Digital Wagner L609 Moisure Detector to measure the moisture content of my HW and Plywood subfloor (30 yrs old - 2 layers - 5/8" and 1/2"). I am shooting for no more than 4% difference between the subfloor and HW. Is this a good target???

I have also found that the readings on the subfloor vary from place to place so have been taking a number of readings in each 4x8 section of plywood... averaging them and marking each section with the average of the readings. The sections so marked range about 6.5% to 9.5%. Is this much variation normal and acceptable???

The Wagner meter is calibrated for Douglas Fir and readings must be adjusted for other species. Tables are provided with appropriate corrections for different species but I'm not sure which species to use.

There are a number of different White and Red Oak species listed in the HW section of the correction tables and the corrections vary significantly. Can anyone tell me what particlar specie (or species) Bruce uses for this particular product (CR3455)???

Also "Plywood" is not specifically listed in the tables. What, if any, corrections should I use for readings on the plywood???

I look forward to any replies and suggestions. ZT

That wood is a mixture of red oak and white oak.

Delmhorst instructed me to use the SPF/COFI species for checking pine plywood subfloors.

Standard OSB corrects using Basswood species
AdvanTech corrects using American Elm species.

which city are you in?

Thanks for the info Jerry!

I spoke to Wagner Electronics (mfg of the L609 M/M) this morning and received the following recommended specific gravities for correcting moisture readings on plywood... I hope this info helps others.

Plywood: Douglas Fir or Southern Yellow Pine CDX > S.G 0.57
Standard OSB: Douglas Fir or Southern Yellow Pine > S.G. 0.70

As for a proper correction factor for the unspecified "Mix of Red & White Oak" in the Bruce Prefinished H/W, I plan to use an average of the values given in the tables for each of the specific species of Red & White Oak.

Do others agree this approach should get me in the (right) ballpark or am I making this too complicated?

I appreciate any replies and suggestions. ZT
(I'm in the burbs west of Chicago)