Hi Amina, Is it drywall dust or glue that's stuck between the boards? We underwent a major renovation of our new old house this past year...and I remember panicking when I saw the filth on my dark hardwood floors. A dry vac picked up all of the white dust that had settled between the boards. It was labour intensive work...I was on my hands and knees vacuuming every single hardwood edge. And then I swept again and once again was on my hands and knees with damp towels.. On the stairwell and second floor, our contractors had put protective covering on the floors to protect them. The glue from the covering was stuck on many areas, and, as Redroze suggested, we used rubbing alcohol to spot clean. It worked. Good luck,

I've seen some parquet flooring that I love! Mine not so much. It's your typical thin red oak basket weave and only in the main area. When I pulled up the carpet I found loose sections of flooring and missing pieces. Along with sloppy cuts around doorways and trim. I was unable to find someone willing to repair it and so my bf has been helping me work on it. That type of floor is a total headache!! It has its share of uneven pieces, gaps and misaligned squares. You'll be able to tell what was repaired. Plus the replacement pieces won't match the original but at least that sections will be hidden. The stain is not my style and won't match other rooms but I will live with it. It's a love hate relationship for sure! I keep telling myself all these imperfections give it character and it will be great when it's done ;)

Your satin has turned from a high-gloss satin to a low-gloss satin (yes...they have different gloss levels and yet are all called "satin"). I've found that a freshly apply satin almost looks like a semi-gloss. It can take 2 months or more before the "real" finish appears (aka the "satin" finally turns satin). If this sounds familiar, then you are bang on schedule for what has happened. In other words this could be entirely normal. Your level of care appears normal. The "cleaner" is only to be used 1/month (once per month) and then rest should be damp mopping with water only. To do a quick check to see if this is cleaner residue (yes...too much residue can dull a finish so you should check for it) go ahead and dampen a cotton ball with RUBBING ALCOHOL and give a 1ft x 1ft square a good cleaning (please ensure you are doing this in a large, well ventilated space and not a tiny area where the fumes can build up. After 5-6 cotton balls worth of rubbing alcohol in one spot, you can then monitor that spot throughout the day. If there is NO CHANGE to the "dullness" then you are looking at the real finish = 100% pure Satin. If the spot appears glossier, then you have cleaning residue which needs to be stripped. Bona offers a lovely stripper. It is nicer than working with Rubbing Alcohol but with a nastier price tag. That's how you figure out if it is cleaning residue or 100% Satin normal. And no - rubbing alcohol does not damage the polyurethane. Please stop applying the cleaner to the floor. You should be applying it to the mop head and then pushing around the mop head. There is no need to apply cleaner directly to a hardwood. Just a little FYI for DIY.

Denatured alcohol should work and if you don't have any of that, then rubbing alcohol. This is assuming that the floors are finished with an oil based topcoat. If the topcoat is waterborne or water based, then I would just use water and elbow grease.