In a 30 year old house that I purchased, the oak wood floors had all been polyurethaned a while back (perhaps 30 years ago?) and they had turned yellow.
We hired a floor refinishing company to sand, seal (1 coat), and urethane the floors (3 coats) using water-based products. I believe they used "Bona" products.
It looked and felt nice.

That was done around February. Now, the floors are no longer smooth in that the seams or joints where the wood planks meet have something that has risen a bit. Its not uncomfortable to walk on, but the smoothness feel of the floor is gone. I am also concerned that my new child, once she begins crawling, will scratch her legs or at least irritate them. The planks themselves are smooth, but the areas where 2 planks meet have something hard slightly rising out of it.

The company that did the work said it was normal and not to worry about it. They said it was due to the humidity levels of the house being higher since its now in the summer.

I wonder if this is indeed normal and what, if anything, can be done to return the floors to their completely smooth feels.

Thanks for any insight you can shed on this predicament.

Once the filler starts pushing out, there is nothing you can do, but call the company that filled the floor diring a time of dry heating, when the gaps were there biggest. They should have known better, they are the professionals.

Because that filler is in there it could cause your floor to look like it is cupping. Which could lead to compression setting the floor and the cupped look will not go away.

That filler can be sharp with the finish on it, and cut you good. I would not let a child on that floor, until the company that did it, removes it.

If your not going to keep the interior of your home in somewhat constant humidity levels, with humidifiers in the winter, and dehumidifiers in the summer, expect gaps during the winters when the heat is turned on, and swelling in the summers.


I seriously can't believe they filled that floor at that low of moisture content. Uneducated contractors, feeding you a line of BS, to cover their Ass-ets.


They should have explained to you why filling the floor at that time of the year is not a good idea, and educated you why. Or had you sign a waiver of liability that they would not be responsible for what is now happening.

I'd call him and ask for his liability policy, again. Because you could be filing a claim soon, if somones foot gets sliced open.

Thanks for the reply Floorguy.

When you say "until they remove it", are you saying they remove the rising filler or are you saying remove the finish and redo the whole process?
If there is a way to remove only the filler, does it require multiple steps or is it just a buffing and nothing else needs to be applied after?

Of course I am hoping that the whole process does not need to be redone.
In fact, they just completed 3 more rooms this month. Perhaps, due to them doing that during the summer with no A/C on, the "rising" problem will not occur in those rooms. It sounds like you say there'll be gaps in those rooms in the winter, but I imagine there's really no way to avoid some imperfection when the humidity and/or temperature changes.

Does this problem exist only because its a water-based finish as opposed to an oil-based finish?

Thanks again for your help.

The only way I know of to fix this is to resand and fill now during the humid months, where the flooring is swelled to its greatest widths, which means a total sand & finish.


Wood is hydroscopic. Meaning during the winter and the heater is turned on, it dries the interior and the wood floor. Yes you will see gapping, or with waterbased finish, can make white lines and or finish peeling at the gaps, because waterbased has more elastic properties then oil, it tries to stretch the finish.

I may have been editing my first reply, when you were posting.

Floorguy,

I reread your first reply and I agree you were probably editing it as I replied.
And thanks again for your reply.

You are talking about "filler". Just to make sure we are talking about the same thing, is "filler" something different than the sealer and urethane finish they apply? They did not "fill" anything before doing the sanding or sealing or urethaning. But perhaps when you say "filler", you are referring to the sealer and urethane products that would end up filling any gaps in the floor boards.

But as I think about it (and keep in mind I am not a floor professional....just a home owner) , I don't know why there would have been gaps since the floor was smooth and had been finished previously with oil-based products. Would sanding have removed the oil-based products from the seams between the planks or would the water-based products would just lie on top of whatever was in the gaps before.

Thanks once again

What ever is in the floor gaps is being compressed out. If the floor never did it with the Old finish, then it is something applied by the refinisher.


Filler, wood filler, wood putty


After snading to bare wood, it is common to trowel fill the floor with wood filler, then resume the sanding squence. This gives the surface of the wood that flat perfect like glass finish, without burning through a lot of wood surface, to get the deep imperfections.

Filler gets down into the smallest of cracks to the biggest of cracks.

If it was coated with a waterbase and it got into the gaps without filler, the compression will also squeeze it out of the gaps, which could very well be what is happening. It might not be filler at all, but just finish that ran into the smallest of gapping. Oils don't do that much but can happen, as petroleum can be compressed, but water can't.