Q: We are currently refinishing our white oak floors. Four rooms are completed after sanding (with 36, 80 and 220 grits), staining, and sealing with water-based gloss polyurethane. Three rooms look great and one room looks tie-dyed. The floors are blotchy with light, dark, and milky spots.
The stain dried for 48 hours before sealing and the room was cleaned with vacuum, broom and tack rags. This room looks so bad we only did one clear coat to date. Why do our wood floors look tie-dyed, and how can we fix it?
A: For one thing, your grit selection is all over the map. It is rare that I use anything rougher than 40 grit. However, you should not skip more than one grit in the sanding selection. From 36 you skipped 40, 50, 60 right to 80 then missed all the other grits and jumped to 220. There likely isn’t any consistency in the sanding and that is reflected in the stain itself. This job is best left to those who have a lot of experience and do this for a living.
Streaks, blotches, and areas lighter than rest of floor
Q imported from our old site, Face Lift Floors: We’ve just sanded our 50-year-old oak hardwood floor. After giving it a quick wash with TSP and applying a gel stain, it’s got areas, not just streaks or blotches, that are significantly lighter than the rest of the floor. Is there anything we can do to spot-fix? Should we sand the whole thing again or just rewash with TSP?
A: How did you sand your floor? What did you use? The areas that are light in color tell me that the stain did not penetrate equally because there was still finish on the floor in the lighter areas.
This sort of job is not quite the same as sanding a little table top. It is best left to professionals who have spent years learning, and thousands in equipment to try and get the job done right. Even with all that, sometimes things go wrong. What was your reason for using TSP first?
Original / moved link https://faceliftfloors.com/q-and-a/spots.php
Lighter and darker spots all over
Related Q: We recently had our oak hardwood floor done by a professional company. Our floor has light and dark spots all over it and it looks terrible. It’s also rough to our feet, not smooth at all. They used only 2 coats of a water-based finish. Is this normal and how can we fix it? We expected a hard, shining, smooth surface and it definitely didn’t turn out that way. Also, they left blobs of stain on the floor.
A: This doesn’t sound good. The light and dark areas of the stain, barring pet stains, is sanding and preparation error. The Darker spots were not as smooth as the lighter spots so absorbed the stain more. The only way to fix that is to start over. 2 Coats of water born finish? In my opinion, it’s not enough. Water born coatings are lower in urethane resin than oil or solvent based coatings so will not provide as thick a film. I generally use Poloplaz Primero which contains about 48% polyurethane resin solids. A typical water born may contain 32% or less.
I don’t like chewing on guys and there is no way to do a 100% perfect sand and stain job regardless of how careful a person is in their work. But light and dark blotches and rough floor? That is a contractor error in my opinion.
Stain not even
Similar Q: We had brand new oak floors put in and hired someone to stain and poly them. We noticed that some areas the stain didn’t take too well (it’s not even). Does the entire floor have to resanded, stained and poly’d?
A: That really depends on the amount of area that doesn’t look right. If it is large areas across the floor then yes, it will have to be done over.