Hardwood floor installation techniques
Hello All,
This is my first visit – have subcribed to the magazine for years. I am hoping all the “experts” out there can help me make sense of the conflicting information I keep getting concerning installation of a hardwood floor over a concrete subfloor. I want to install 1,000 square feet in my 20 year old home located in Southern California.
Some retailers have told me I should only install an engineered wood – not 3/4″ solid wood – using special glue to a concrete subfloor. They have also told me installing over plywood layed on the concrete is a bad idea and not cost effective.
Then I have had other retailers tell me laying plywood down is OK. Some say just nail down the 4×8 sheets. Some say they must be glued down and nailed. Some say you should only use tongue and groove plywood sheets. Some say use 4×4 sheets only. Some say you need to score the plywood every foot with a 3/8″ deep cut. Some say nail every 2-3 feet, some every six inches, etc., etc., etc.
WOW there seem to be so many different opinions. Are they all correct? Or is there a best way. I plan to be in my home for the rest of my life. So I would like to find the PROPER way to install the floor and still be cost conscious.
Thanks for helping a confused Bampa (grandpa).
Replies
bampa,
I hate to tell you this but you're going to get just as many conflicting opinions here..
If it were me I would do the job as completely as possible! yes to tongue and groove, yes to a vapor barrier underneath, yes to hardwood floor not engineered wood.
do it right, do it right!
frenchy, can you provide some further deatails. he will need more info than that. he needs to check moisture content. the house is old, so curing is not an issue, but we don't know if it is a damp basement floor.
vapour barrier , then plywood subfloor. is he going to nail thru the plywood making holes in the vapour barrier making it pointless? you may have some pocedures, that are affective, but please clarify.
Alrightythen,
since it is California dampness isn't the issue it would be here. I like overkill whenever possible simply because that's the kind of person I am.. belt, suspenders and a properly fitted pair of pants is the way I approach things.. Can he get by with less? Certainly! I dislike glue down approaches because I've been in afew homes where the glue has given up and it's painful to walk across those floors the snapping and cracking of glue drives me crazy..
Engineered wood? Not in my house, to me it's like vinyl siding siding, fine for some but Not for me, that's just something the next person will tear out (or he will when he tires of it)!
You've got some good points theere, but remember you have monster beams in your house that most people will never even see, let alone thingk of having in their house.Engineered is not the same thing as real wood, but for the average house, glued down engineered will outlast many other portions of the place.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
not sure why french discourages non engineered, I don't know a ton about it, but I believe it is a favourable choice over slab. ( from what I have heard)
my hardwood installer, likes to glue down hardwood over concrete. check for moisture content. 0 percent is great. but 1 or 2 willl be ok. if he starts getting up to 3 then he likes to use a sealer over the whole slab - let it cure before glue down.
1 or 2 years ago FHB ran an article on gluedown over concrete. not sure the issue number but you could try an article search, or maybe someone will know.
OK Bampa,
Heeere we go!!!
assuming hieght is NOT an issue...
Lay down 2 layers of 6 mil poly
then put dow 2 layers of 5/8 cdx ply wood
1st layer good side down
second layer good side up, staggering joints in both directions
Glue and staple the layers together to form a 1-1/4 floating deck.
them lay yer hardwood on yer deck.
I believe there was a article in FHB about this years ago.
maybe someone here has figured out the FHB cd and can find it for you
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The Aristocrats
Thanks for the input thus far. My slab is ground level - not a basesment, no such thing in So. Cal.
If I understand Mr.T correctly all I need to do is lay the moisture barrier followed by the two layers of 5/8 plywood then simply nail the 3/4" solid wood oak floor as you normally would do.
No GLUE or nails attaching the plywood to the floor - just let it float - correct?
Does the plywood need to be tonge and grooved or is just but joints good enough since we are using two layers of plywood?
Can I use 1/2 plywood instead of 5/8?
Bampa
Bampa, I believe you understand T's post correctly. No need for t&g, just offset all the joints, and use staples that won't poke through the VB. Two layers of 1/2" would work okay, but you may need shorter cleats. The 5/8" layers will allow 2" cleats to not poke through.Yes, the plywood sandwich just floats on the VB.Bill
Thanks agian for the feed back from every one.
Bill, "Cleats," are these the nails that hold the 3/4" hardwood down?
Does it make any difference what kind of vapor barrier I use - I saw some information on Titebond 531 Epoxy Moisture contrl System. Basically you simply "roll" it on the cement slab with a paint roller.
Also, what is the best procedure for gluing the plywood layers together? What kind of glue and best way to apply? Must every suare inch between layers be glued or just spot gluing?
How far from wall should the plywood be? How far from wall should the hardwood be? Is 1/4" too close?
Should I apply a felt layer between the plywood and the hardwood layer too control squeeking - creaking noises?
Why don't you Goggle "hardwood floor install"? There is all the info you will need. Good luck!
Better off with the 5/8" - and use fir ply - not pine ply.Or use a product called Drycore, then 1/2" ply over that.;)There are inded a hundred variables , but most of what you heard from retailers sounds un-knowledable at best and likely influenced by their need to sell what they had in stock at worst.We don't have anything to gain, so we're all angels here...Ha
Watch out for that frenchy. The only thing he remembers from California is when he was a Sun God and the women worshipped at his feet, so his thinking about California floors is warped by the memory
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Piffan,
Say what? Sun God? women worshipping at my feet?
Ha! I was in the Navy during the peak Vietnam years.. over a million sailors marines and other servemen in the area and something like 30,000 single women under the age of 30 I rarely saw women and they darn sure wouldn't worship me!
You must be thinking of yourself <G>
Bampa
Dont let anybody tell you that engineered flooring is some cheap alternative.
I just left Texas where they have as many slab homes as you do in Cali and glued down engineered floors are very common. Dont mistake good engineered flooring for some of that cheap laminated type stuff - its not the same creature.
Doug
This is the site for the Assocation of wood flooring manufactors. Select ALL publications and then hit search.
You can download the How to Install manual.
http://www.nofma.org/Publications/tabid/82/Default.aspx
These are the general accepted approved methods. Now individual manufactors might have different requirements.
It give several different ways of installing solid wood floors on slab. IIRC one is the floating plywood that has been mentioned. Others include plywood on sleeper and I think on where plywood is fastendown.
There are some other information on vapor barriers, etc that might be useful.
I don't believe that they get in to any engineered wood flooring, but not sure.
But remember solid wood over plywood would end up increasing the floor height by maybe 1 1/4" to 1`3/4". If this is an existing house then you need to think about how that would affect transistion to other floors, cabinets with toe kicks and stairs.
Engineered wood floor is 7/16 to 3/4" and can directly on the slab (depending on the installaiton options).
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
http://www.hardwoodinstaller.com/hardwoodinstaller/hardwoodonconcrete.htm
One thing that would help is if you would make a couple of decisions. Like, do you want solid or engineered? Do you want it glued solid to the concrete, or do you want a more traditional nailed installation?
If you use two layers of ply and engineered flooring, you can get quite close to the walls. If you use solid flooring, you should stay about 1/2-3/4" away. In either case the ply can go to less than 1/2".
"Put your creed in your deed." Emerson
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt