Hey,

I stumbled upon this forum searching for information after I had my engineered hw floors refinished recently.

When the entire process was finished, the very first time we saw when entering the house was a pronounced ripple effect in every single area which was redone...

When we went in to view the floors before the stain and finish, there was no visible issue.

We spoke with the company who did the work and they went on an on about how amazing the finish is and how high tech their sanders are and how perfectly calibrated they are and that this "issue" happens 70-80% of the time and there's nothing you can do about it.

They never disclosed even the potential for this to happen to us when we spoke with them about having the work done. And now, because they're engineered floors, they say they can not even sand them down again even if we wanted to have someone redo them.

In our house we have engineered hardwood with a cork underlay which is glued to a cement floor.

Essentially what I am looking to determine is;

should this have happened or was it a bad job?
what could have caused this to happen?
is there anything I can do?
is the guy trying to worm his way out of doing anything by feeding me garbage about how good the job was done?

I appreciate your thoughts,
Thanks!

When you say "ripple effect", that makes me think "chatter marks". Small lines across the grain of the wood,approx. 1/4" apart.

If this is what you were describing,these marks were left behind by a drum sander that was either worn badly or out of balance.

We use orbital sanders on engineered wood. This process only removes a thin layer of wood,allowing you to refinish the flooring about 3 times, usually. If they sanded your floor with a drum sander, chances are they cut off way more wood than necessary.Engineered only has a thin layer of real wood on top, so they may not be able to refinish,depending on how much they sanded off, how many times it's been sanded, etc.

You definitely should not see ripples. A refinished floor should be smooth,with no sanding marks whatsoever.Yes,we do occasionally find floors with sudden slopes,pitch changes,humps,dips,etc...and these places sometimes can be hard to sand without leaving some small marks.However,an experienced finisher knows what to look for,and should take measures to remove the sander marks before any stain/finish application.
If it were me, I'd try buff sanding just down to the wood surface.If these are sander marks,they can most likely buff them out with minimal sanding on the actual wood surface,although it won't cut the finish off as fast as a drum sander,it works nonetheless.
If they have this issue 70% of the time, then I'd say 70% of the customers are left unsatisfied.
Bottom line - you should not see anything that drastic. An occasional ripple is expected,but to the untrained eye, it should look perfect.

Thanks for the reply!

I have been doing some looking online and I too believe chatter marks are what we're dealing with although I could be wrong... From what I see, they're further apart then 1/4", I would say more like 1-2" apart... Are they any other type of conditions which look like chatter marks?

Also, they do not run with the grain of the wood, our boards run East - West and all the marks run North - South... From what I can see, it looks like they didn't even sand with the grain of the wood, they sanded across each board from right to left...

This was the first sanding but according to the company which did it, they can not sand it again.

According to them, it happened because our floor is on cement which caused vibrations... As I said before, our floor is concrete, and then there is a layer of cork to which the floor is glued to. The floor is also full tongue and groove...

We see the marks in all kinds of light.. natural, ceiling light, almost no light from any regular standing position and it goes all the way across the room, in every single room... The funny thing is that this re-finisher was actually recommended to us by the flooring manufacturer.

The guy said it was perfectly normal and offered us some free area rugs for our house and then started talking about what would happen if we took him to court... We just want our floors to be done correctly... If it was a small issue, it wouldn't be such a big deal but the fact you can see it in every room from every standing position, you see it all the time.

Its the first thing we see every time we walk in...

Thanks!

You're describing your floor as a floating floor.And yes, because the flooring isn't fastened to anything , it can be tricky to sand. However, it shouldn't have chatter marks all over it.Chatter is almost always the fault of the contractor in that he is not very good at his job or his Big Sander is poorly maintained.

As far as what you can do, you can try re sanding a small area with a low powered sander like a clarke OSB 18 which is a square buffer basically .Also, there 's the option of using a disc buffer with a hard plate on it.A disc buffer has more power and may be able to cut out the chatter without cutting through the wear layer of your flooring.

Courts and lawyers are all pretty crooked so winning in court is usually more about strategy and intimidation than it is who is right or wrong.And law suits are costly so proceed in that direction after having a NOFMA approved inspector look at your flooring.

I also want to know about Refinish Floor. This page provides some useful information for me. Thanks!