New floor using old floor as subfloor.

There is an existing sub-floor underneath the parquet. Does the floor squeak or have soft spots? If so - pull it up and repair sub-floor underneath. Will an extra 3/4" of height create transition problems at bathrooms, kitchens & doorways? If so, pull it up. The new floor is only as good as it weakest layer.

fatrabbit:

1. I have replaced a number of parquet floors with new wood planking
2. in each instance I removed the old floor and its sub-base
3. unless you do so your new floor might squeak a lot, annoying your neighbors
4. it might have other problems as well

i would remove the parquet, unless you're sure that you are selling within 5 yrs. when you lay the new floor down, you need a good base.

Another vote for removing old floors.

Structures are only as good as their foundations. If you have to rip it up and do it the right way later, your total cost will be higher.

Good luck

If the existing parquet is solid -- no gaps, no squeaks, no waves or dips, no loose pieces -- AND you won't have an issue with transitions to other existing floors in the apartment, then just leave it.

You should have a pretty high bar for keeping it in place, but to say it absolutely needs to come out is overkill.

What if the old floor is tile/marble? In good shape just not modern.