I just purchased a red oak floor for my livingroom/dining room (small area, 350 sq ft). It is Bellawood Red Oak select 3/4 x 5". ( I wish I found this site prior to ordering it, oh well). I have been getting conflicting ideas of whether or not to use felt paper. I was told by Lumber Liquidators, that due to the width of these boards, to install the floor using both glue and nail to prevent cupping. (There is a full basement below and this is not a new construction, the new floor will be sitting in my place for about 2 weeks prior to me installing it). The current subfloor is plywood (5/8" to 3/4", it is hard to tell at this point). Any thoughts??? Glue would have no effect if it is just stuck to 15lb felt paper. Has anyone had any issues with the 5" wide Bellawood?

Anyone selling a nice used Bostich or PorterCable Pneumatic floor nailer in the Long Island NY area???

Before flooring can be installed, the moisture content of the subfloor should be within 4 percentage points of the flooring that will be laid on it.. If the moisture content between the flooring and subflooring varies more than 4 percentage points, then the flooring should not be installed. It's not a time issue. This is where numerous LL installers even get in trouble. You need a pin meter.

Drill a hole though it or look in a vent for proper thickness.

Haven't had any issues with the 3/4" x 5" Bellawood cupping, performing a naildown installation over 15 pound felt, no glue. Ofcoarse after proper acclimation and testing, like mentioned, and keeping the RH in your home within range. That being said...I am aware that gluing along with the nailing on wider widths is more of a stable installation when cupping is a concern. I would follow their direction on this, just wondering if they have run into issues in general with 3/4 x5, just the Oak? Or maybe just being cautious. Ofcoarse you wouldn't install felt in this scenario.

On 5" widths, you may want to consider a 2% wood moisture content difference between the wood flooring material and sub-floor.
The 4% difference is used for narrower widths.

The wider the plank, the more likely it is to cup. Slight cupping on 5" width may not be avoidable during seasonal changes.

Yep 2% is better having it the same is ideal. Be aware of the fact that we are getting into the heating season so that means you gota be carefull installing wide planks tight. Lookied at a floor yesterday that was installedin Feb and is now cupped. Everthing was in check just aclimated to the dry enviroment of late winter and now late summer humidity has made it grow almost 1/2" in 10'.

You mean full spread the floor and nail it? Hmmm

Remember to check moisture content of the subfloor underneath in the basement. This will give you a better idea of whats going on down there and the potential for more moisture rising through the floor. Just because the top is within your target number means nothing.

Course I know a guy who only has rosin paper under his oak floor and his basements totally floods a couple times a year and it does nothing to his floor...no movement, no cupping.

To answer "floormeintucson", the guy at Lumber Liquidator said to use Loctite PL 400 in a zig-zag pattern on each board as well as nailing every 6". I checked the subfloor and it is 2 layers,one 1/2", one 3/8" (cant figure out what the builder was doing in this Condo complex??? ) Due to the fact that no one lives above or below me, sound suppression is not a factor.

I am still considering using the felt paper and forgoing the glue but, no decision yet. MY basement does get a little humid during the summer months, even with a dehumidifier. Im hoping than nailing every 6" would suffice. I rather have an occasional squeak in the floor, than deal with cupping and buckling during the summer months.

I know at some point I just have to make a decision and go with it.

As of now, I am still prepping the subfloor (removed carpet, screwing down floor, checking for high/low spots) so i still have a week or so to make a decision. More opinions the better.

Love this website and everyone who is contributes to it.

Thumbs up to everyone

I may have missed something.
1. What region of the country do you reside? If you have a heating season followed by a humid summer season, be careful and I would suggest glue and nail as suggested earlier.
2. Rosin or felt paper are not moisture retarders, they are there for sound and noise. Vapor moves through felt and rosin paper. I wrote an article published in the NWFA Hardwood Floors Magazine on this issue. Too many believe felt and rosin paper are moisture retarders resulting in failure after failure.

Thank you Ray for my oversight, I live in Long Island, New York.

Course ply is typically 2% lower than solid when using a pin type meter. And you must try and read a level plane to avoid reading different plys, can be different species in the plys. OSB is...well I guess you don't have OSB do ya. Then of also you need to avoid meter reading drift. And in double errrr multiple sheathed wood substrates one would need to get core temp readings a various depths (eg. gradients/insitu) for true documentation purposes.

Then if you want to get reeeally anal about testing the subfloor you can employ species correction factors for different species (if you can identify) used in plywood and then there's some for hybrids too.

But you should be fine if you can get hold of a professional pin type meter.


editied: to much info

SpeedNut:

Long Island area has summers of high relative humidity and winters (with use of heaters and cold weather) of low relative humidity.
The RH swings from the 70's to the 20's.

Changes in relative humidity results in changes in the wood moisture content.
Changes in wood moisture content result in shrinking and swelling of the wood flooring.


Basements on Long Island are usually wet due to the elevation of the Island and age of the homes.

The Industry standards dictate no more than 2% difference between the wood and the sub-floor.
Industry and manufacturer installation standards allow for either nail down over felt or glue and nail as suggested by LL. Both are within the standards. I suggest glue and nail due to the area you live in.
- I would also suggest installing the wood at a wood moisture content of 8% or 9% (the upper range) as it is better to have some gapping than excessive cupping.
--- Installing at too low a moisture content would result in cupping next summer as the wood swells and has no place to grow to so the edges compress and give a cupped appearance. (I think i saw just such a suggestion on this already).

YOU MAY HAVE TWO DIFFERENT ENVIRONMENTS.
1. Upper floor.
2. Flooring over the basement.

I think your best bet is to go to www.NWFAcp.org and hire a local Certified Hardwood Installer who is familiar with your unique environment and buildings. NWFA certified installers are usually dependable and knowledgeable.
I suggest a local company simply because they know the in's and out's of your particular area.

What works in California would result in failures in your area.

I did moisture measurments with a pin meter. Subfloor averages 8.5, I used samples
from both manufacturing runs in my order and averaged 4.5 (uh oh!!).anythoughts about removing the floor from the boxes? I also saw on this site of someone using playing cards to space the boards to allow for some expansion. I understand I'm being a little OCD, but that is the type of DIY person I am.

Yes, removing the planks from the box will help allow the wood to gain the moisture content needed.

Curious:
I thought you explained that there are two levels in the home.
My question:
What is the moisture content in the sub-floor directly above the basement compared to the sub-floor in the upper level?

Is this a full basement ??

Please don't take one moisture test and consider that one test the premise used to install the floor.

It is best to perform pin meter tests in random areas and then average them.
Compare the readings over the basement to areas not over the basement..

I think you get the idea.

So Ray, are you saying to just go in and take a pin measurment or even multiple measurements and thats it? No EMC chart, how many number of measurements per 1000sf, calibration, no temp readings? Is that how you do inspections? How do you come up with that 2% figure?

Thanks for the info Ray. The 8.5 was the average of the entire area where the floor is to be installed (temperature 68 degrees,about 30 different readings ranging from 7.8 to 9.7) It is a middle condo unit with a full basement and an second level above. I cannot access the subfloor on the second level unless I rip up the carpet which is only a year old so not quite ready to do it. Any ideas about the playing card idea?? It seems to make some sense in this scenario.

Again, many thanks to all if the professionals on this website. I have been telling my friends about it.