Underlayment?

[walnutjerry]

In my current DIY project (complete kitchen redo) It involves replacing the underlayment. Question is, what is the product being used most often now in residential work? particle board, OSB or plywood?

My house was built in 1966 and the underlayment was 5/8" PB. Seems that thickness is available in OSB and plywood but not the PB. When I started searching for underlayment I was told to use what the floor covering manufacturer reccomended or it would void the warranty of the floor covering. The supplier of the floor covering did not know the answer.:BangHead:

Do we have any members that are "up" on underlayment material? Vinyl roll goods will probably be the covering.

Jerry

 

[Ray Martin]

Jerry,

The only product I use for subfloors is an OSB-like substance called AdvanTech. It's stiffer than OSB or plywood and very resistant to swelling due to moisture. I've put down subfloors and had standing water on them for a week with no swelling or other breakdown. Here's a link to the folks who make the stuff... http://huberwood.com/main.aspx?pagename=advantechflooring

I'd recommend a thick bead of construction adhesive on every framing member, under the subfloor. This is a three person job, with one dedicated to the gluing (the other two to lug the sheets of AdvanTech around). The glue skins over in a minute and is then MUCH less effective. Keep an extra 2 X 4 and a long handle sledge hammer nearby to gently persuade the sheets of subfloor into place. The AdvanTech is tongue and groove.

While AdvanTech holds nails much better than particle board, I'd also suggest you use ring shank nails, at a minimum, for fastening. Without the glue and ring shanks, you'll have a squeaky floor.

Ray


Ray

 

[Bernhard]

Jerry,

Ditto what Ray said. I used this forr the sublfoor for the second floor in my house. I think advantec is a GA Pacific brand, there are similar board from Weyerheuser, etc.
Before I bought these boards ( they are a bit more expensive than ply), I took a cutoff, weighed it and held it under water in a bucket for a week. After one week under water there was about a 4% weight increase, no noticable swelling or deterioration.
The only thing I like to add is that I used srews. Screws tend to pull the board down to the substrate and spread the adhesive out. I was afraid that nailing it down would not evenly distribute the adhesive bead and lead to a wavy floor.
Cheers,
Bernhard

 

[Travis Porter]

A lot of times you have sub floor and I guess what you call "under layment". The sub floor stufff I would agree that Bernhard and Ray are right on. For the underlayment, a lot of times you see 1/4" luan plywood (which I now hate) or there are some 5x5 panels you buy and screw down. That will give you a bit more thickness and less bounce IMO.

 

[Alan in Little Washington]

Travis has a good point- are you talking underlayment or subfloor. Will you be laying whatever you get on the floor joists or on a subfloor (traditional bias 1X6 or ply)? If you are talking subfloor then Advantech is the only way to go! That is all I have for a floor in my shop. It is smoother, denser, more rigid, and MUCH TOUGHER than OSB (and ply) and really water resistant- it is made with a waterproof binder or epoxy.

Now if you are talking underlayment for tile or carpet, that is something else all together- most of that stuff is 1/4 or 3/1" and 6isn't too durable- I have seen ply, Luan ply, hardboard, and thin MDF used.

 

[Nativespec]

Luan plywood is a good choice. The warranty on a vinyl floor can't be worth much.

If you are only doing a section of the floor, I would patch it and use some leveling concrete. If you are going to tile over it, I would suggest the "Wonderboard" and not worry too much about the patch. It all depends on the type of finished floor. Sometimes you will come accross some old flooring that is next to impossible to rip up. In this kind of situation I would put new plywood over everything after replacing a rotted area.

David

 

[Ray Martin]

We're starting to debate the merits of various approaches... and we forgot to ask what the requirements are.

Will the flooring material be hardwood? You'll need something that will hold a nail or staple. AdvanTech fills this bill. Will the subfloor be covered with wall to wall? Particle board is probably going to be the least costly and will do just fine under carpet. Will the finish be vinyl goods? Use Luaun because it is very flat and very smooth (Even the smallest bump will telegraph through the vinyl.) Luaun generally comes in a thickness of 7/32s. You'll need AdvanTech under it. Luaun should also be stapled down... every 6 inches across the whole field.

Ray

 

[walnutjerry]

My house was built in 1966 and the underlayment was 5/8" PB. Seems that thickness is available in OSB and plywood but not the PB. When I started searching for underlayment I was told to use what the floor covering manufacturer reccomended or it would void the warranty of the floor covering. The supplier of the floor covering did not know the answer.:BangHead:


Jerry

Ray---------the finished floor will be vinyl (12' wide roll). My house has SUBFLOOR of diagonal 1x sheeting of various widths, then a layer of tar paper for a moisture barrier (the area is over a full basement), then it HAD particle board for UNDERLAYMENT. I have taken all the old PB up because the vinyl would not come off it and I did/do not want 1/4" underlayment. The old underlayment was nailed every 4" into the joist which are 16" on center and no adhesive--------we never had a squeaky floor in 42 years. Maybe it was the tar paper that kept it from squeaking-???????????

David-------I am doing about 350 sq. ft. that takes in the kitchen, dining and hall. To match the adjoining living room area I need to stay with 5/8" thickness.

Alan------If Advantech comes in 5/8 thickness, I could go for that. I have not searched the site yet to see what thickness is available.

Travis---------I do have subfloor as stated earlier and I do not like the 1/4" thing either.

Bernard------Not sure I will use adhesive. I do not have any helpers on this but I have a nail gun and plenty of ring shank nails:rolf:.

Thanks guys for all the good input and advice:icon_thum----------things have changed in the construction world over the years. I just have to use the nearest best material to acommodate 40+ year old house.

Jerry

 

[alleng]

in your case,if the diagnal 1x4s stay,id go with 5/8 plywood,then 1/4 luan. if it is stripped to the joists... advantec is wonderful stuff.just use adheasive to eliminate squeaking. ive soaked a pice in a bucket of water for a day,and no swelling. i use scrap pices for tool stand tops. it stays flat and true. and it has a 50 year guarentee:icon_thum

 

[walnutjerry]

Alan----the Advantech is available in 19/32 thickness!! So------------I will be looking for a supplier that carries that thickness. Thanks again guys for the tip.

Jerry

 

[Tarhead]

Jerry,
Check Lowe's for the Avantech. I'm not sure the thickness (?3/4") but I'm pretty sure I saw some in the Concord store. They have a $10 off 50 deal so buy as close as you can to $50, get a coupon, go back, buy $50, etc.

 

[Gotcha6]

I'd use 5/8" PTS(plugged & touch sanded) PW in the kitchen area. It should say 'underlayment' on it. Particle board & water don't mix too well over time & the inevitable plumbing leak or spill will cause problems. Use screws long enough to go into the floor joist 1 -1/2" & countersink the heads. A good floor man will take care of the joints & screw heads. Also, if you have pets in the house go ahead & use it everywhere. Pet urine will soak through carpet & PB is porous enough to leave the smell there indefinitely. Under roll vinyl goods it's OK but if it won't break your budget just give yourself some peace of mind & use the PW throughout.

 

[scsmith42]

A good brand of plywood subfloor is called "Plytanium", I think by Georgia Pacific. It's generally considered to be the plywood equivalent to Advantech.

 

[NCPete]

I second Scott's suggestion of the Plytanium. but in new work, where floor heights will not be negatively affected, I like the newer 7/8" plywoods.

 

[Ray Martin]

Some good suggestions in this thread. I think the thing you have to consider after laying in a subfloor that won't squeak, is to make sure the underlayment is VERY smooth. That's the reason I like the Luaun skin over the AdvanTech. Whichever way you decide to go, use some leveling compound to fill every void, nail dent, seam, etc. Any bump or divot will telegraph through the vinyl.

Good luck with this

Ray