We had natural, horizontal bamboo installed over a cement slab, using glue adhesive. It is starting to cup consistently across the entire floor (1000 sq feet). The slab was dry and there is no apparent moisture source as far as I can tell. But, I don't think the installers let the bamboo "acclimatize" properly prior to install. I'm also not sure if they left the appropriate gap between the wall and the floor to allow for expansion. I have two questions: 1) will it continue to get worse; and 2) is there anything that can be done to fix/minimize the cupping?

THanks.

From the description mentioned it sounds like the wrong adhesive was used. Is there a brand name?

I think it was Roberts adhesive. Once that ran out, they used Henry wood floor adhesive.

Your insteallers must have been supplying the adhesive and bought the cheapest stuff they could find. Unfortuunately, your installers are now responsible for buying you new bamboo, tearing out the stuff they stuck down with the waterbased glue, and purchase the moisture cure urethane that is about $150 for 5 gallons instead of the $ 30 for 4 gallon stuff that was the wrong glue.


Never use an acrylic/waterbased adhesive with bamboo or solid wood!!! Or you buy the customer new wood and you get to tear out and eat what you just put in.

Roberts makes a urethane, but I doubt that is what was used. Probably 1404.

That stuff has lots of water in it. Heck, I have seen it screw up engineered wood when plenty was used.

will it cause a major problem - ie will we have to tear out the floors, or just a little bit of cupping that we can deal with? Thanks.

actually, i just checked it 1407 - acrylic urethane is what it was. could it be another problem?

Besides that being a major, major problem, the substrate could also have too high of moisture emissions. I doubt they even checked!


You got HACKED! No if's, and's, or but's about it!

All acrylic and latex wood floor adhesives are for ENGINEERED floors only, and even then they can cause problems because of the water in the adhesive. IF the concrete does NOT have excessive moisture emmission, the bamboo flooring MAY return to normal but it is doubtful. Generally, once a floor cups pretty good, it rarely goes back to it's original shape. The cupping MAY go down a little but probably not completely flat.

Is there anything that can be done, outside of ripping out the floors? Would it help to put weights (books/bags of sand) on the floors. At this point, the cupping is not too bad, but I want to prevent it from getting worse. The floors were just installed last week.

Thank you.

Audrey,

With it being only a week it is hard to tell if you will expereice more cupping or not. If it is just the moisture in the glue than chances are yes you have seen the last of the cupping and the damage you have now is all you will see. As for your questions about alternatives to ripping it out there are alternatives and it depends on how bad the cupping is and how spread out it is. If it is a small location then the cupped boards can be cut out and new boards installed. If it is all over but the cupping is light the floor can be sanded to remove the cupping and then refinished. Unfortunately weights, books, or bags are not going to save you; if the damage is extensive then the floor must come up.

Thanks for your advice!

Audrey,

I put almost 800 sq feet of carbonized bamboo in my downstairs townhome almost 8 months ago. I got it from afforda floors and me and a freind put it down. We used the Bruce enginereed floor adhesive that you buy in lowes & home depot and glued it to concrete. I haven't had any problems with cupping.

Most of the bamboo stuff is engineered and not prone to warping like solid wood, but I let the bamboo flooring sit in my home for almost 3 weeks before I put it down. My townhome was 3 years old and not a brand new construction, so I'm assuming my concrete was dry enough not to cause problems. I never measured it with a moisture meter.

I'm no expert in flooring, but I'm inclined to think it either has to be the wrong type of glue, or your concrete was not dry enough. When flooring pops up like that so quickly after being installed, I don't know how it could be anything else, other than a very sloppy installation job.

It is very important to open the box and let the bamboo planks acclimatized to the local climate. The installer should be responsible for the problem if he haven't done the work.

Well its too early to pull the chain on this project.
First thing, is the concrete slab elevated, or on, or below grade.

If the floor cupped almost immediately after install, there is a chance that as it releases excess moisture from what MAY be the wrong glue; it could lay down flat given time, and dry environment.

If the concrete slab is the culprit, introducing too much moisture to the floor, then you are faced with full removal.

Right now: wait and see, give the floor a couple weeks to stabilize; then revisit your options