After much research, I decided to have a Kahrs product floated over my concrete subfloor. I chose Kahrs' Doussie Dakar which is a tongue+groove (glue together) design from their Castle & Cottage collection. After some small patchwork to subfloor lowspots, my installer opened the packaged flooring to find planks that were bowed (regardless of their length)- we both raised flags. According to our telephone conversations with the flooring dealer, distributor and Kahrs, they said bowing in the engineered plank was normal (huh??!!). In any event, they recommended we continue the installation as see how the bowing is reduced once planks are joined together. Well, my installer put down a 2'x20' area before i asked him to stop his work. There was too much bounce/sponginess to my liking. You could see a 4-5' section move when walked on (in more than one location). On Monday, the old flooring gets removed and my replacement flooring gets delivered-- I've opted for the Kahrs Cherry Genua from the 2 Strip Woodloc collection (click together). According to my installer, the Woodloc product will give him the ability/option to spot nail the plank to the concrete subfloor in areas where there might be too much up/down travel.

Details - Floor #1
Subfloor: concrete slab
Underlayment: Floor Muffler
Flooring:Kahrs Doussie Dakar [SKU 141M15DO40KE130] 1-strip design, silk matte finish, bevelled edge, 3-layer construction
9/16” x 5” plank

Details - Floor #2
Subfloor: concrete slab
Underlayment: Floor Muffler
Flooring: Kahrs Cherry Genua [152N55CH50KW] 2-strip Woodloc, 5/8" x 7 7/8" plank, 3-layer construction

Finally, my questions:
1. Shouldn't engineered wood planks be true and perfectly flat?

2. I expect my floating Kahrs floor to look/feel/sound like a traditional 3/4" hardwood floor when properly installed. Are my expectations too high?

Any thoughts/views/feedback would be much appreciated. Many thanks to Ken for this website and forum! dbj

Guys like to call them banana boards. Yes it is common, but depends on the severity. The overall weight of the floor itself, once installed should take care of it. Was the subfloor properly prepped in accordance to flatness tolerances?



On concrete? A floating floor? That's a non-no.

1- I've seen it with short length engineered hardwoods too, but if it's minor it should be of no concern.

2- Depends, some can notice it, others cannnot.

No offense, but I believe the main problem here is your installer. It would appear that the prep work done on the slab may be inadequate.

No qualified installer would even "think" about fastening down a floating floor.

I'm not there to see it but it sounds like the slab is not flat enough. As Ken said the weight of the floor will hold itself down and the flatter your slab the less noticeable it will be that the floor is floating. But it will never feel like a solid nail down.

Chicago has lots of installation related problems for some reason.

I'm in agreement it is your installer!!


Ya, of all the failure I have problem posts, Chicago is leading the way with bad installations.

Is it the same guy installing these failures?

Major red flag here. Do not let him nail that floor down it is asking for trouble.



I don’t think I have seen an engineered that did not have some bowed boards.



Yes. It is not a ¾ nail down; it is more affordable engineered floating install, there are trade offs it will look like a ¾ but it is not going to feel nor sound like a 3/4. Glue down would get you closer.

Just installed a Kahr's Castle and Cottage yesterday and was surprised how many boards bowed up in the middle. Not what I expected at that price. ALl the boards were straight along the T&G side and it went together well, though. Now that it is down, no problems with bowing. The weight brought it down.

If you think of how the boards fit together, as you fit the boards together, the bowing will go away as the boards on each side of the bowed one bring it down when they fot together, so I would say definitely the subfloor is not level enough. Maybe it is level within one or two feet, but get out a 4 foot or longer straight edge and you will see the problem.

Get an 8 foot or longer straight edge. I use a 10 footer, as that is the measurement on the specs, or at least it was 3/16" in a 10' radius.

What do you recommend getting for a straightedge? I have seen the pics of the aluminum one you have, is it sold as a straightedge or is it some other piece of hardware?

Thanks so much to all the posters, the information here is great.

It is an aluminum ceramic tile screed.

I purchased it from my flooring supply house.