# glue down on concrete - question



## JohnHomeMatters (Sep 20, 2008)

Hi.
I'm a GC, not a flooring expert. Client found a hardwood specialist he likes with a good price on the flooring he likes. I'd like to ask you about a couple of things the contractor intends to do because I don't know enough:

Installation will be engineered, unfinished Brazillian cherry glued directly to concrete slab. On the stairs, he will use a product called "New Stair" that he says allows him to convert prefab stairs to oak for staining.

1. I asked about a vapor barrier. The contractor says he has a special glue that handles that, and use of an additional paint-on type barrier would negatively affect the glue down.

2. Is the "new stair" product for prefab stairs (meaning not site built) a good product?

3. Contractor says prefiinished flooring tends to fade so he doesn't use it. Only uses unfinished wood that he finshes on site.

Does it all sound right to you? Thanks for any advice.


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## bwalley (Jan 7, 2009)

Whenever we do a glue down engineered floor on a slab on grade we use MVP as a moisture barrier, no matter what the mositure tests say and then use Bosticks best glue.

Not familiar with the stair product.

It seems to me that prefinished flooring would be more resistant to fading as in a factory they have better control over the finishing process.

A wood floor that is installed sanded and finished onsite if done correctly looks better than a prefinished job IMO.


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## the big 12 inch (Jan 22, 2009)

You should be able to go right over the slab as long as it is dry and clean if you are using a good poly glue like bostiks.I always glue down my unfinished wood and let it sit for 10 days or more before sanding and finishing to allow the glue to acclimate with the wood to minimize exspansion and contraction issues...If job is below grade...your on your own!!..Good luck..Iv'e never heard of the stair product either..


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## JohnHomeMatters (Sep 20, 2008)

Thanks for your responses. I have since learned that the installer plans to use Mapei 980, which he believes is similar to Bostik's Best. According to the Mapei website a vapor barrier is only needed if the slab fails a moisture test. I don't know that the installer has or plans to do a moisture test. I wonder if anyone really ever does that?

Here's the info on the stair product -- it's a good product from what I can see: http://www.nustair.com/installation.aspx


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## rusty baker (Jun 14, 2008)

Not much of an installer if he doesn't run a moisture test.


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## bwalley (Jan 7, 2009)

JohnHomeMatters said:


> Thanks for your responses. I have since learned that the installer plans to use Mapei 980, which he believes is similar to Bostik's Best. According to the Mapei website a vapor barrier is only needed if the slab fails a moisture test. I don't know that the installer has or plans to do a moisture test. I wonder if anyone really ever does that?
> 
> Here's the info on the stair product -- it's a good product from what I can see: http://www.nustair.com/installation.aspx


You should put a moisture barrier down, no matter what a moisture test says.

It is cheap insurance.


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## Mike Costello (Aug 1, 2004)

Mapai is ok and cheaper, not great. Bostiks Best is great. ( try getting it off your hands!)

Dont let him put that floor in until he test the moisture content of the slab and the wood your putting in.

For the few extra dollars a moisture barrier is smart insurance no matter the result.

I have been using Dependable's Cut Down as a moisture retarder. You apply a few coats of it, with a roller, in opposite directions and it gives you a nice clean hard surface to glue to.


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## astor (Dec 19, 2008)

He has to test the moisture content of the slab and the wood.There are different test options for that-chemical or mechanical-.Slab must be 28 days or older.Unless the house sitting clay bed and have moisture traces all over,in and out,you will not need Bostik MVP,test first to see the moisture level on slab.
For the stairs treads and risers,he has to use a stair jig no matter what brand/type he is planning to use.Stair Jig looks like this.http://www.amazon.com/Wheaton-Tools-PL200-Stair-Wizard/dp/B0000224Q2/ref=sr_1_4?ie=UTF8&s=hi&qid=1255815477&sr=8-4
I did not notice prefinished fades more than unfinished all these years,Brazilian cherry will darken and get deep red within couple of months and stop darkening.
There are Brazilian Cherry solid (laminated real wood)stair treads,risers in the market,which will match with flooring,fading it from oak (by staining)is not acceptable for my clients,but they are mine,depends on customer.I usually finish them in my shop and then install on site.
But every flooring guy has his own way.:laughing:


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## mrghm (Nov 19, 2006)

i did a big job this year we tested the slab, no sealer required. floor cupped as it was poorly made (bamboo). i just replaced all the floors at my cost as my suppiler said the floor failed due to the slab not being sealed.

to date i have spent 125k replacing floors and in legal fees against my suppiler.

if i win against the supplier then i will get my money back if they dont file for bankruptcy.

all jobs now get a sealer even if the slab is 100yrs old.


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## Staging (Aug 22, 2008)

There's a floor contractor around my area that installs 1/2" plywood on the slab. After the plywood he installs felt paper and then glues and nails the wood floor. The plywood is glued and nailed to the slab. Has anyone seen this method done.


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## Mike Costello (Aug 1, 2004)

The plywood in itself will not deal with the moisture . I am not a fan of nailing any wood to a concrete floor. If you rolled a moisture retarder - it can be comprimised by the nails. Same to be said about a poly barrier.

Its a step that brings up other issues like clearance and doorway transition issues.


I know some guys like to nail when they can because its easier to make a tight floor as you go. But for my time and money gluing wood to a properly checked and prepared slab is better than layering wood for the sake of nailing.


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## bwalley (Jan 7, 2009)

Staging said:


> There's a floor contractor around my area that installs 1/2" plywood on the slab. After the plywood he installs felt paper and then glues and nails the wood floor. The plywood is glued and nailed to the slab. Has anyone seen this method done.


That is because he doesn't know what he is doing, his method makes no sense.

If you want to do a glue down, you don't put down a wood sub floor.


When you install a wood sub floor over top of a slab on grade, you install the felt paper, then 3/4" T&G plywood, then nail the floor to the wood subfloor.


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## bwalley (Jan 7, 2009)

mrghm said:


> *i did a big job this year we tested the slab, no sealer required.* *floor cupped* as it was poorly made (bamboo). i just replaced all the floors at my cost as *my suppiler said the floor failed due to the slab not being sealed.*
> 
> to date i have spent 125k replacing floors and in legal fees against my suppiler.
> 
> ...


That is why I always use MVP, no matter what the moisture test says.


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## the big 12 inch (Jan 22, 2009)

We used to use mastic,felt,mastic,felt..then 3/4 plywood then the wood floor...Did they cup?..you bet yer ass they did!!


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## Staging (Aug 22, 2008)

bwalley you are right. Do you perfer to install the subfloor over the slab or do you install a sealer and then the wood?


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## Floordude (Aug 30, 2007)

JohnHomeMatters said:


> Thanks for your responses. I have since learned that the installer plans to use Mapei 980, which he believes is similar to Bostik's Best. According to the Mapei website a vapor barrier is only needed if the slab fails a moisture test. I don't know that the installer has or plans to do a moisture test. I wonder if anyone really ever does that?
> 
> Here's the info on the stair product -- it's a good product from what I can see: http://www.nustair.com/installation.aspx




This guy sure wished his installer had done a moisture test.


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## JK Floors (Mar 15, 2009)

Floordude said:


> This guy sure wished his installer had done a moisture test.


Or left an expansion gap? Looks like flooring is butted up against the wall and cabinet in both pictures.


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## KG007 (Oct 23, 2009)

*Installer is 90% right...*

Your installer sounds like he knows what he is doing, but has some personal preferences coloring his opinions. May not be wrong, just opionated. First, probably does need to do a moisture test(s) if there is any doubt, but I assume he may have already done so.

Most glues for hardwood on concrete contain a moisture barrier as part of the formula. Assuming what he uses is like this there is no need to use a sealer.

I'm leary of "sealers." In many cases a sealer must be REMOVED before gluing down - otherwise it prevents proper adhesion and the glue may peel up like paint. (I've seen paint peel up on a sealed concrete floor, luckily before we glued down wood on another part of the suite.)

I've never seen anyone use an engineered UNFINISHED wood, though I suppose there is no reason not to. My question is how thick is the wear layer? Many engineered woods have a very thin wear layer and if you sand very deeply you are up **** creek. I disagree that a sand & stain floor gives a finish superior to prefinished. The opposite is true if all other factors are anywhere close to comparable. Same wood, but stain is applied under controlled factory conditions, typically 7 to 10 layers of poly plus aluminum oxide instead of just 3 layers of poly done on-site.

Biggest reason people say they like a S&S floor is the square edges instead of beveled edge on prefinished. Is your engineered unfinished floor square-edge or beveled? Installers tend to treat unfinished wood rough, counting on the sanding to make up for "boo boos." So a lot of installers don't like prefinished because they have to actually take care while installing.

Prefinished floors will not fade any faster than S/S. The reverse is probably true, but any floor will change color - look at any of them where part has had a lot of direct sunlight, covered by an area rug, etc. The quality of the wood and finish regardless of prefinished or S/S probably has more impact.

One of my vendors has added the stair tread things you describe and I'm thinking about adding a display. Haven't installed any, but everything looks good about them. Essentially is cheaper/faster/easier to install over particle board or pine treads than tearing out the staircase, having a finish carpenter install new treads, then sanding and finishing.

As far as nailing plywood over concrete so you can nail down a solid hardwood floor, I think doing so is goofy. I know people who have done it and claim it came out okay, but I have my doubts and think most will develop problems of some kind down the road. Just goofy - it's usually someone who doesn't know jack about anything except 3/4' solid trying to get around his limitations. But that's just my opinion...

Good luck!


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## bwalley (Jan 7, 2009)

Staging said:


> bwalley you are right. Do you perfer to install the subfloor over the slab or do you install a sealer and then the wood?


If it is an engineered glue down, we use MVP moisture barried no matter what the moisture test says, the we glue the floor down with Bosticks best.

If we are doing a nail down, it can be either solid or engineered, we install either MVP or felt paper then nail down 3/4" T&G plywood, then nail down the flooring, if we aer worried about sqeking floors we will install a layer of felt on top of the plywood, then install the floor.


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## Floordude (Aug 30, 2007)

mrghm said:


> i did a big job this year we tested the slab, no sealer required. floor cupped as it was poorly made (bamboo). i just replaced all the floors at my cost as my suppiler said the floor failed due to the slab not being sealed.



What makes you think it was poorly made? Who told you you didn't need a moisture barrier with bamboo?

Concrete has the ability to be cooler than dew point temperature, so if you slab tested within specifications, and you documented it with pictures and a job log, what does the slab test now? What changed, beside your wallet getting lighter.

Bamboo always gets a moisture barrier, even if the slab test OK, as dew point can make it cup.


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## Floordude (Aug 30, 2007)

bwalley said:


> When you install a wood sub floor over top of a slab on grade, you install the felt paper, then 3/4" T&G plywood, then nail the floor to the wood subfloor.



That would be a recipe for a failure here!!!

You need a non-compromised moisture barrier under the plywood, asphalt saturated felt is not a moisture barrier. It will retard moisture transmission, meaning it slows it down, but with concrete vapor emissions, it does not eliminate moisture getting to the plywood and flooring.


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## Floordude (Aug 30, 2007)

grahaminteriors said:


> Most glues for hardwood on concrete contain a moisture barrier as part of the formula. Assuming what he uses is like this there is no need to use a sealer.



Urethane glue is a good moisture barrier, if you build it thick enough. As a single application, using the recommended trowel, you do not get enough thickness to have enough perm rating. The trowel also has teeth that scrape the concrete practically clean, leaving the notching ridges of glue. There is no perm rating at the bottom of the ridges.
So you have been some what misinformed if you believe the adhesive is also the moisture barrier. Maybe Stauf 960, but not any other adhesive.





grahaminteriors said:


> I'm leary of "sealers." In many cases a sealer must be REMOVED before gluing down - otherwise it prevents proper adhesion and the glue may peel up like paint. (I've seen paint peel up on a sealed concrete floor, luckily before we glued down wood on another part of the suite.)



I think your real confused or misinformed.
The "sealer" as your calling it, is not a sealer. It is an epoxy, or urethane coating, compatible with the same manufacturers adhesive. 






grahaminteriors said:


> I've never seen anyone use an engineered UNFINISHED wood, though I suppose there is no reason not to.


You need to check out Owens, or Real Wood, brands. Quality stuff!







grahaminteriors said:


> Biggest reason people say they like a S&S floor is the square edges instead of beveled edge on prefinished.


One word... Lauzon prefinished sq. edge Hardwood
Owens, too


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## bwalley (Jan 7, 2009)

Floordude said:


> That would be a recipe for a failure here!!!
> 
> You need a non-compromised moisture barrier under the plywood, asphalt saturated felt is not a moisture barrier. It will retard moisture transmission, meaning it slows it down, but with concrete vapor emissions, it does not eliminate moisture getting to the plywood and flooring.


It is a very common practice to do this in Florida on slab on grade nail down applications.

The slab's already have a vapor barrier underneath it.


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## Floordude (Aug 30, 2007)

bwalley said:


> It is a very common practice to do this in Florida on slab on grade nail down applications.
> 
> The slab's already have a vapor barrier underneath it.




YIKES!!

You have been misinformed!!!

Since all concrete has moisture vapor emissions, where is your moisture barrier that is *REQUIRED* on top of the concrete?

You really should take some formal classes. I suggest Howard Brickman's excellent class. After the class take the test for the NWFA.


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## KG007 (Oct 23, 2009)

*"Sealer" vs "Moisture Barrier"*

Quick note re: Floor Dude's comment above. There is a difference between a "sealer" that some concrete contractors (or painters or whoever) put on concrete and a moisture barrier. The SEALERS I've come across dry clear and you usually can't tell they are on the concrete. I suppose these are to 'seal the pores" so to speak of the concrete. the result is they have to be ground off if the floor is going to be painted or have an adhesive put over it, though you may suceed with a lot of adhesives. That's a calculated risk I'd rather not take, because if it fails it is going to be on you as all the glue manufacturer's will claim you didn't prep the floor right.

There are multiple brands of hardwood glue that say they are also a moisture barrier and nothing else is needed. If you want to use some other kind of moisture barrier with it be my guest. I've never had a problem with any glue down hardwood because of moisture (knock on wood), but any extra insurance is good. My only question is if it voids the warranty - not that most manufacturers will honor a warranty anyway.

I ran into one issue a couple of years ago. The concrete had some additive that is supposed to create a "skin" on the surface to hold moisture IN the concrete during the curing process, then breakdown and allow the moisture to evaporate after about 30 days. Supposedly makes the concrete stronger.

We had a job where the concrete was slimy wet and originally attributed it to the lousy autumn weather which was miserable with rain. Thought the houses may have been built over a spring because of being in a low spot, or just hydrostatic pressure. After talking to the project manager we find out about this additive and it was just breaking down and allowing evaporation after about 90+ days instead of 30. 

So when someone says "sealer" or "moisture barrier" or "skin" or anything else you better ask questions and find out exactly what they mean.

I've seen, and have carried at times, some square-edge prefinished products. I don't see anything as a big plus or minus on them, but have to be more careful than ever on installs. Even if you use one of these products a client that has a prejudice against prefinished is still not going to like them because of cracks they want filled in with poly.

The reality is prefinished is better than S/S - same wood but more coats of poly applied under controlled environmental conditions with aluminum oxide. But we do both, and either type can come out great, or come out crappy due to poor quality of the product and installation. I've seen more floors screwed up on S/S because of poor installation. With prefinished screw-ups are more from poor quality product than bad installation.

We just finished 1100+ Sf of a decent prefinished and the wife is giving me total hell. Almost three weeks after completion before I could get in to do a walk through and punch list - the husband had a stroke two days afterwards and she claims its my fault. Reality is the floor looks nice but has a short punch list. Only one area where I have any real issue with the installation, up against a wall where the nail gun couldn't be used. In 1100 SF found two boards installed with very minor cracks in the finish that didn't get caught and culled (the largest was about 3/16" x 1/4").

Upshot of it is they wouldn't have been happy with anything except S/S, like the rest of the house, but then would have been unhappy with it taking longer, moving out of the house while it was finished, the dust, and the smell. The wife admitted that and says they made a mistake in selecting what they did, but still thinks I'm Satan or worse and it's all my fault. So once again proves that problems are often the result of expectations rather than actual problems. Hope the GC who started this gets some useful info and brings the homeowner into the process or he can get unhappy clients no matter how good the job.

P.S. I have 3/4" Brazilian Cherry in two places in my house. It's great, but every batch of wood will darken differently. Never seen any stain on Br Cherry, just poly. Be extremely careful of the quality of the wood, there is some cheap crap on the market (like bamboo). Some of the mills in this region have stopped producting Br Ch, or have resumed in only 3" and 5" widths. I've seen some cheap crap 5" solid cup before the homeowner ever moved in. Our area isn't great for doing over 4" solid because of the big seasonal changes.


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## KG007 (Oct 23, 2009)

*Another issues with exotics*

One other issue with exotic woods. With poor quality woods you might get spots that appear on the floor several months to years after they are installed. This is from minerals in the wood where the tree grew and manufacturers will NOT warrant against them. If it looks like a spot of dried milk in the finish that won't come out odds are good that's what it is.


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## Floordude (Aug 30, 2007)

grahaminteriors said:


> There are multiple brands of hardwood glue that say they are also a moisture barrier and nothing else is needed.



Besides Stauf 960, care to provide the proof needed, to back up your statement? Multiple, means more than one. Please list the multiples.
As a NWFA failure investigator, I have seen your thinking lead to many many failed installations.

Bostik's doesn't
Mapei doesn't
Frankin/Titebond doesn't
Taylor doesn't

Stauf 960 is the only adhesive that markets and advertises it is a one application moisture barrier and adhesive. It is only good to 8# per 1000 sq.ft. of moisture vapor emissions.

Bostik's MVP and Mapei WFM, are capable of restraining much higher emission levels.

Franklin's is a 2-part epoxy coating that is rolled on.

Taylor's is the use of there MS+, letting it cure out, and then another coat for adhesion to the wood.

Why would these adhesive manufacturers make a moisture blocker, if their adhesives where a stand alone, one application moisture barrier and adhesive?


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## Floordude (Aug 30, 2007)

grahaminteriors said:


> One other issue with exotic woods. With poor quality woods you might get spots that appear on the floor several months to years after they are installed. This is from minerals in the wood where the tree grew and manufacturers will NOT warrant against them. If it looks like a spot of dried milk in the finish that won't come out odds are good that's what it is.



Then you dealing with some shady manufacturers!!

I have never had a claim denied for silica deposits(milky looking spots and streaks) That is a defective board. Usually associated with Jatoba.


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## TopFloor (Apr 21, 2009)

grahaminteriors said:


> ...I've never seen anyone use an engineered UNFINISHED wood, though I suppose there is no reason not to. My question is how thick is the wear layer? Many engineered woods have a very thin wear layer and if you sand very deeply you are up **** creek...


I start an unfinished, engineered hickory in a couple weeks. The wear layer is 3/16". Thats not bad. Can you tell me how much sanding is afforded by, for example, a 3/4" solid plank?


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## cprao (Oct 23, 2009)

I am also researching on my client request to install patagonian rosewood (Exotic) for the adhesive and Moisture barrier. The shop recomments Stauf 960. SInce this is very expensive ($250 per 4 Gal) and he requires 5 tins (20 gals for 700 Sq Ft), he asks me to look for alternatives.. I only found this '1407 Acrylic Urethane Latex Adhesive' in Home Depot But this is not a MVP. It is just a adhesive. Can I use Bostic's MVP and them Home Depot's Adhesive ? I am still not sure would that be any cost effective for him ? 

I am confused as to what should I suggest my client who is very conservative..


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## Floordude (Aug 30, 2007)

cprao said:


> install patagonian rosewood (Exotic) for the adhesive and Moisture barrier. The shop recomments Stauf 960. SInce this is very expensive ($250 per 4 Gal) and he requires 5 tins (20 gals for 700 Sq Ft), he asks me to look for alternatives.. I only found this '1407 Acrylic Urethane Latex Adhesive' in Home Depot


You went WAY downhill there.

You do not want an acrylic, unless it is an engineered wood floor.
If you have never worked with an acrylic, your in for a very big surprise!


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## cprao (Oct 23, 2009)

Floordude said:


> You went WAY downhill there.
> 
> You do not want an acrylic, unless it is an engineered wood floor.
> If you have never worked with an acrylic, your in for a very big surprise!


It's a engineered wood. But still the question is can I use Acrylic and Bostic MVP ? Does this combination makes sense and cost effective ?


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## mrghm (Nov 19, 2006)

Floordude said:


> What makes you think it was poorly made? Who told you you didn't need a moisture barrier with bamboo?
> 
> Concrete has the ability to be cooler than dew point temperature, so if you slab tested within specifications, and you documented it with pictures and a job log, what does the slab test now? What changed, beside your wallet getting lighter.
> 
> Bamboo always gets a moisture barrier, even if the slab test OK, as dew point can make it cup.


 
installation sheet said less than 4% MC no sealer required. slab tested 2 to 3% at 60RH.

the bamboo also failed when it was installed on the same project over a raised plywood substrate.

the construction cleaner also wet washed the floors after they were installed.


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## KG007 (Oct 23, 2009)

*How much sanding?*



TopFloor said:


> I start an unfinished, engineered hickory in a couple weeks. The wear layer is 3/16". Thats not bad. Can you tell me how much sanding is afforded by, for example, a 3/4" solid plank?


I'm not an expert on S/S, rely on the crew I use who is for real detailed questions. But I think your answer is "it depends."

On 3/4" solid you can sand it until the nail heads appear, then you put in a new floor. The nails are inserted at an angle through the tongue, so your amount of usable/sandable wood is what, maybe 1/4" to 3/8" give or take? So on your engineered hickory I guess the question is how thick is the wear layer OR where do the nail/staple heads come to, whichever is less.

As far as how many sandings, it depends on how good the person doing the sanding is and any factors specific to that floor. Using a good crew that doesn't take that much off each time on a well maintained floor I would guess one could get as much as 6 to 10 sandings over the life of the floor. Considering most people don't refinish floors as often as they need to, that might be a hundred years or more.

However, a floor may cup from environmental conditions or water damage, etc., and may need a lot more taken off in a sanding. Could be the equivalent of 2-4 normal sandings, maybe? I'd like to hear from some experienced installers who do this every day and hear their opinion. Also, if the person doing the sanding uses a heavy hand, or someone has put bad swirls or gouges in it, or you go deep to try to minimize pet urine or water stains, you are shortening the life of the floor, but those are fixing problems and you probably don't have much choice.

I've only had one floor where the nail heads popped up when we put the sander on it that hadn't shown obvious damage, and it was circa 1920-1930. Other option: if there isn't actual damage to the wood and you don't have to SAND, my understanding is you can screen it and refinish it as many time as you want, plus it's cheaper. 

Just my guess, but I'd say most floors are going to be torn out or something else laid over them or get catastrophic damage before a homeowner has to worry about too many sandings. And if it is 80 years from now, you won't have to listen to the crying. Good luck. I'd love to see some photos of the finished floor.


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## KG007 (Oct 23, 2009)

*Better get a sub who knows what they are doing...*



cprao said:


> I am also researching on my client request to install patagonian rosewood (Exotic) for the adhesive and Moisture barrier. The shop recomments Stauf 960. SInce this is very expensive ($250 per 4 Gal) and he requires 5 tins (20 gals for 700 Sq Ft), he asks me to look for alternatives.. I only found this '1407 Acrylic Urethane Latex Adhesive' in Home Depot But this is not a MVP. It is just a adhesive. Can I use Bostic's MVP and them Home Depot's Adhesive ? I am still not sure would that be any cost effective for him ?
> 
> I am confused as to what should I suggest my client who is very conservative..


Not sure I can give you real good advice here except to first get a REALLY GOOD sub who specializes in this. Sounds you are in a field you aren't used to, so find someone who does know it.

Second, if your client wants to put in a really expensive floor and then cheap out on the installation and materials, I suggest either walking away from the job (give his money back if you have to), or at least have him sign in writing that HE is directing you use something other than the recommended materials and methods and it's all his responsibility - and will cost more for the installer and you to take the risk/pain of dealing with him.

Third, who is the wood manufacturer and what do they recommend? You are likely to void any guarantee if not done their way with what they recommend. If the client bought some no-name stuff, or off the internet or Lowe's/Home Depot crap, better have him sign off like above if you are still willing to do the job.

Forth, my rule of thumb is 90% of what you might buy from the box stores is probably junk. I suppose you CAN get good stuff, but odds are against you no matter what it is.

Fifth, I've never even had it suggested about using an acrylic on hardwood, so I can't comment except to ask why you want to use an acrylic adhesive on it? I have used an acrylic wet-set adhesive on luxury vinyl plank to see what it was like in a "wet area" near a shower. The installers DID NOT like it and from what little experience I've had with it I concur that you want to stay away from it if this is your "starter project" for using an acrylic unless you have to.

Sixth, most manufacturers have instructions and recommendations and technical support llines. They usually say warranties are void if you don't use their brand adhesive, etc. So if you don't do exaclty what they describe you have NO chance if there is a claim. (Not that they are likely to honor a claim anyway...) 

Summation - sounds like you are assuming the risk of replacing this floor out of your pocket if anything goes wrong, and you don't sound sure of how to approach this project. I strongly recommend re-reading points one and two above. Having said all that, do you have any other alternatives? This may not be the floor for your client, especially if he is bitching the cost of the proper adhesive is make-or-break on his budget. Best of luck, I know it can be frustrating to try to get a client to listen.


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## Floordude (Aug 30, 2007)

mrghm said:


> installation sheet said less than 4% MC no sealer required.



4% using what method of measurement? A Calcium Chloride dome test?






mrghm said:


> slab tested 2 to 3% at 60RH.



Again using what test method?
60rH, did you do a "Hood" measurement?




mrghm said:


> the bamboo also failed when it was installed on the same project over a raised plywood substrate.



Sounds like it didn't fail to gain moisture content, after it was installed. It gained it just fine.:laughing:
How are you suppose to stop bamboo from gaining more moisture content, which makes it expand, after it is installed?:whistling




mrghm said:


> the construction cleaner also wet washed the floors after they were installed.



Why are you placing blame on the bamboo, then??:shifty:
Why didn't you say that in the first place??
Swab the decks, matey!:w00t:


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## TopFloor (Apr 21, 2009)

grahaminteriors said:


> ...I think your answer is "it depends."...Just my guess, but I'd say most floors are going to be torn out or something else laid over them or get catastrophic damage before a homeowner has to worry about too many sandings...quote]
> 
> :thumbup:
> Ding! Ding! You are correct, sir.
> ...


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## KG007 (Oct 23, 2009)

*RE:Wood adhesive/moisture barrier in one*



Floordude said:


> Besides Stauf 960, care to provide the proof needed, to back up your statement? Multiple, means more than one. Please list the multiples.
> As a NWFA failure investigator, I have seen your thinking lead to many many failed installations.
> 
> Bostik's doesn't
> ...


 
I pulled two buckets in my warehouse and both brands describe the trowel, floor prep, etc., with neither saying anything about needing a second product applied for anything else, including a moisture barrier. One, Mannington Ultra Spread, describes it as "...tough, flexible, water resistent, ..." and Mannington's installer handbook (as I remember without looking it up) and summarized installation instructions on the glue and hardwood all say use Mannington's glue only. I've had Mannington tell me anything else will void a claim (though they will squirm out of any responsibility anyway), which includes if any other product of any kind is on the floor.

Parabond's Millenium 2002, according to the label, describes similar installation except wet-lay. Again, makes no reference to needing any other product or moisture barrier. Surprised me because I didn't realize that Millenium is "Acrylic Utherane Wood Flooring Adhesive" - hadn't registered on me it is an acrylic.

Installers hate the Mannington glue, love the Millenium 2002. The Millenium is also a lot cheaper and, in my limited experience, is a lot easier to work with and a much better product. Maybe this is what the guy dong the rosewood needs???

As for "shady manufacturers dodging claims on mineral spots," I was told directly by a Mannington-hired inspector they wouldn't cover it- so maybe you are right! Mannington has never wanted to even talk about claims when I've had ANY issue, no matter how slight, and I'm pursuing action against them for screwing me over a teak floor that I replaced once out of my pocket and immediately failed again. Manufacturing defects! Every single thing they claimed was a problem absolutely is untrue. That's why I've dropped Mannington.

I've also used the Mohawk brand glue (which costs more and didn't work as well as Millenium) and while I haven't bothered to look it up as I don't have a bucket or tech sheets handy, at the time we followed instructions andit was essentially the same as Mannington or Millenium regarding no reference to needing any other product used in conjuction. Nothing wrong with the Mohawk brand, but costs more and not quite as easy to work with - since we were using a low cost wood on 6-8 houses I decided to risk using Millenium instead, figured it was a problem I would claim against Millenium (Parabond) and/or foot it out of pocket.

On the teak floor, since it was very expensive, we followed Mannington instructions to the letter and the floor, and replacement floor, had major problems and failed each time within 3 weeks. They had changed the wood, thickness of wear layer, no telling what else, and it was a piece of %^&#, then ran the other way.

I haven't made a big study of whose glue requires what or how because of not needing to. But I've never had it even broached that a separate moisture barrier was needed. Sounds like different approaches in different parts of the country, which actually surprises me some with what I thought was a fairly common product and application.


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## Floordude (Aug 30, 2007)

grahaminteriors said:


> I pulled two buckets in my warehouse and both brands describe the trowel, floor prep, etc., with neither saying anything about needing a second product applied for anything else, including a moisture barrier. ...blah, blah, blah




You missed the part on the bucket, about moisture measurements and limits.
Guess who make Mannington's wood adhesives?? It ain't Mannington.

Would you care for me to link it here for you?


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## KG007 (Oct 23, 2009)

*Don't think I missed anything...*

Sorry I didn't quote the entire label off a couple buckets of glue. Somehow I thought there had already been extensive discussion about moisture tests and not doing anything at all until moisture levels are within acceptable bounds. Or maybe I should pull out the entire installer handbook and quote a chapter or two. As far as who actually manufactures various brands I don't really care, I'm sure there is a lot of out-sourcing. The point is there are multiple ways to install a glue down floor. If you want to use two-part glues and that works or that's what the manufacturer designates, I've already said I think that's great - I'm all for extra "insurance." My point is there are brands that say they also act as a moisture barrier and, in my experience which doesn't cover every floor in the world but is a decent sample, we haven't had any moisture problems because of following these directions. From what I've read on this blog different brands and different syles of wood or installation are in favor in different areas of the country. Sorry you don't like it.

Problems I have encountered with these type floors have had other issues, but I'm sure I will encounter moisture issues no matter what we do if we eventually install or look enough of them.

One thought for the guy with the rosewood floor - have you thought about floating the floor? I've done a couple and had good luck EXCEPT for in the corner of a sunroom that had apparently no insulation in the wall and you could feel cold air whistling through in the winter. Caused uneven expansion/contraction and gapping in that corner. If you decide to do this be very careful about having a LEVEL floor - charge extra for floor prep!


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