Polyurethane Oozing Out On Newly Refinished Hardwood Floors

Question:

About 3 months ago I had my floors refinished. Some of the area was old floor and some was new. The refinisher applied 3 coats of oil based polyurethane. Everything looked great. Now the weather has begun to get warmer and excess polyurethane is oozing and bubbling up from many of the seems. If I notice it, I clean it up right away. The problem has occurred when I do not notice it and it gets stepped on and spreads on the floor. It almost seems like it’s now dried on the floor. I’ve tried cleanig it with mineral spirits and that has not worked. Is there anything else that I can do to get my new floors looking the way they should ?

Amy

Answer:

Dear Amy

I’m sorry to hear of your trouble. The cause of the non drying urethane started just after the sanding of the floor was completed. The floor mechanic applied the first coat of polyurethane much too thickly. And then he probably came back the next day and continued to apply more coating. The gaps of an old floor contain lots of impurities (wax, silicone from polishes, etc.) and it’s the first coat of poly in those gaps that never got dried. And then the inexperienced floor mechanic, not seeing this (or ignoring it, to get on with the job) went ahead and sealed up this undried finish. Which is exactly like putting the lid on a can of urethane. You mentioned that the job was done in the winter when the gaps were the widest and now that the floor has somewhat swelled the oozing finish is coming to the surface. Unfortunately it’s a much to common occurrence in this industry, from floor guys who only read the (way too optimistic) drying times on the finish can label. But fail to “read” what happening to the floor itself.

Have your floor mechanic come back about once a week all summer long and use a well sharpened and burnished CABINET scraper to remove all the smeared finish from the surface and the bubbling up new wet finish, as soon as it comes up. It takes time for all this sludgy stuff to work itself to the surface, and the higher summer humidity should help with the squeezing effect. But unfortunately the higher humidity will also make it very difficult to get the finish to cure. So I would also suggest putting on as many fans on the floor as you can muster. Try to keep the temperature of the house above 70F but below 80F and the humidity as low as you can.

Only when the floor has gone about a month or more with no more oozing should you consider screening and recoating the floor. And it I were you I would wait until the winter when the heat is on. I give explicit directions on how to BRUSH on a coat of poly, without causing any bubbles in my famous “Poly w/o the Bubbles” article on the home page. But the key here is to wait until ALL the stickiness is GONE !!!!! Might have the floor mechanic read this article at his expense, eh ?

Another more quick, but expensive way to do the job is to completely remove all the floor finish by chemically stripping the floor. Again one of my famous article on the home page describes the procedure in great detail, using a band name, safe but effective stripper. In your case since it’s poly on the floor, this method is going to take up maybe twice the stripper (50 square feet of floor will be stripped by only one gallon of stripper) and a whole lot more time, than some of the old finishes I was dealing with. So in this case the stripping and refinishing (done by professionals) will cost 5-6 dollars per square foot. Let me know if you are actually going to go this route, as I will have some added instructions in your special case.

The last choice would be to have the floor sanded to the bare wood and left to dry for as long as it takes to get those seams cured. And then finish the floor properly with a thin coat of poly for the first coat, and follow the detailed instructions to the letter in my article. This is also best done by a pro, as the sanding alone will require special sandpaper (open coat 20 grit) so as not to clog up while coarse sanding the old sticky finish off.

And I must stress this is my last and most un-favored choice. Sanding the floor will remove an excess of wood, that your floor may not be able to “afford”. Each resand of 3/4″ hardwood floor remove about 1/6 of it’s life. And if they have to use the very coarse sandpaper, maybe even 1/4 of the entire life of the top of the groove. Just how many sandings your floor has had before, an experience pro will recognize, and determine what is the best route to go. I just cannot see the floor from here, but you could email me some pictures.

As always your Most humble servant, Joseph, the Wood Floor Doctor.