Hello everyone, great site, internet, what a great tool.

Anyway, i live in upper New York and i was planning on putting some Bruce Kennendale Prestige Plank (3/4" x 3.5", solid, eased edge, maple) on above grade 5/8" plywood where carpet was (30 yr old house). The plywood is butted tight on the lengths and has about 1/8" gaps on the widths, i heard you should have 1/8" all round? I'm worried the plywood will warp up in the humid summer months.I do have AC and a humidifier in my furnace but i'm not sure how steady the humidity levels in my house stay through the course of the year (need to get a hydro reader for lack of the appropriate word). I have read that my subfloor is of minimum suggested thickness and wanted an opinion of whether I should add more over the existing for preventive measure.

Should i maybe rip a line with a skil saw down the lengths of existing ply to create expansion gaps?
Anyone have experience with this particular line of Bruce?
Is it a good product?
Have i asked too many questions?
Is there a limit per post?
What is the meaning of life?

Any help is greatly appreciated. (especially for the last question!)

dam no one ever answers my posts, bad luck i guess, o well great site anyway

It's a 30 year old house, that has 30 year old plywood. If it hasn't had a problem yet, no need to cut reliefs.

No need for more plywood unless you plan to install the flooring parallel with the floor joist instead of perpendicular.

I am assuming that the subfloor is in good shape and the joist are a maximum 16"OC.

Maple is a little more unstable species than say, Oak. Your moisture readings for the maple plank and the plywood subfloor should be within 2% of each other.

You will have to keep a check on humidity too. You can get a digital hygrometer at Lowe's for 20 bucks.

Are you over a crawl space?

Thanks for the responses guys,

The joists seem to be a foot apart (thats where the nailing lines are) and the room is on the second level of the house. I've been reading the old posts for a week or so and heard that i might want to leave a credit card sized gap between boards every so often (because i think the house is a bit dryer in the winter which is when i am installing). Is this true? if so, how often to leave the gap?
Jerry are those moisture readers (for the wood) expensive?

Thanks again for the advice, what a great site.

A professional quality moisture meter can run $300.00 or more. There are some lower cost ones but I wouldn't depend on their accuracy. If you acclimate your flooring for two weeks inside your home under normal temperatures (65 to 75 degrees), you should be fine to install your flooring. Your subfloor is not on the ground floor so it should not be gaining any excess moisture from the exterior or ground. IMO, after acclimation, you should be good to go. If you do not have central air conditioning, you may experience very slight cupping of your floors come the late spring (or whenever your high humidity time of year is). This is normal and the floors will return to normal once the humidity is normalized. Try to keep the interior at around 45 to 50 % relative humidity, either with dehumidifiers, humidifiers, or low tech. Fans, boiling water on the stove top, opening the windows, etc. The humidistat can tell you if you exceeding the optimum readings.

i have central air conditioning, and a humidifier hooked up to the furnace, i will buy a hygrometer and see what my readings are in the house and how stable they are. I've been reading more posts (like another 8 hrs tonite, it's very addictive), and i'm thinking that maybe i should go with a type of wood that is more moisture friendly? Is maple a bad choice for that?

thanks again for all the advice, you guys are awesome.

sorry guys one more thing i left out, i heard it's good to use cleats instead of staples (if your worried about moisture swings) is this true
i'm going to buy a MIIIFS does it convert to cleats?

thjnks again

Maple is not as stable as oak, cherry, walnut, etc. In fact, it is one of the less stable woods. But if you keep your interior at close to the same temp and RH, you'll be fine. Flooring contractors in the gulf states often prefer to use cleats due to the wide swings in humidity. Any area that experiences that should consider using cleats. Why? Cleats allow the flooring to move ( they don't hold as well ). Either one will work fine if done properly. The Bostitch M111 is now available as a cleat nailer or you can buy a conversion kit.

thanks gary. i am still amazed at the wealth of information this forum provides. I am truly thankful.