Q imported from our old site, Face Lift Floors: We have had our floors professionally refinished (white oak). There was no stain applied, but an oil-based sealer and two coats of waterborne finish. Most areas look great. There are some areas that have a noticeable color shade difference – For example, fairly long strips where a hand sander was used to remove the prior finish along with a wall edge. Also a few areas mid floor.
It has the appearance of a slightly lighter shade. I assume this is due to a thicker coating of the sealer and/or uneven absorption due to slight differences in the sanded surfaces. Is this normal? If not, what can be done to fix it?
A: If you had said that this lighter shading was around the perimeter of the room, I would say the main reason for this is not enough preparation before applying the finish. the big sander for the main part of the room, and the edger work differently, and the edges usually get “polished” more smoothly. This can show a shading difference unless an orbital sander, as one method, is used around the perimeter to remove this line, and the entire floor is polished with a fine grit screen to make the entire surface equally smooth.
I don’t know why this blotchy look would appear also in the middle of the room. You say this is white oak. Probably also quarter sawn. This can be a tricky and unforgiving wood at times due to the concentration of tannins in the wood. If it is suspected that a problem might occur, then a water-based urethane is the better choice of finishes. However, you mention that they used an oil-based sealer first. How strange! And risky. The one problem with oil-based finishes, when working with difficult floors, is that the solvents in the wood can react with tannins and activate other chemicals that may have found their way into the wood. Water based finished don’t have a high enough concentration of such solvents to be a problem.
If your floor is quarter cut, then the surface is certainly more porous and open, and may also require additional coats of finish. However, you can distinctly tell if the finish has soaked in or is thicker in some areas than others. This is not the same as one area being darker or lighter.
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