new tiles in bathroom

You can. I advise waiting as per instructions on the adhesive

Yes, if you don't install sound isolation you should ask building management or strata associate

No I would at least give it 24 hrs

Yes, it may be possible. If all of the existing tile has already been removed and the floor is properly prepared, a professional installer can use a rapid-setting thinset and grout to complete the installation much faster than a standard tile job. However, the exact timeline depends on the condition of the subfloor and the specific products being used. In many cases, light foot traffic is possible the same day, while shower use may need to wait until the following day.

Yes, it is possible to use a fast-setting thin-set mortar for a small bathroom, but being able to use the bathroom the same day depends on more than just the mortar. The subfloor must be properly prepared, the tiles installed correctly, and the grout also needs adequate curing time. While some rapid-setting products allow light foot traffic within a few hours, it’s generally recommended to wait until the adhesive and grout have cured according to the manufacturer’s instructions before putting the floor into regular use. If this is the only bathroom in your condo, let the installer know in advance. They can recommend the best rapid-setting products and provide a realistic timeline so the installation is completed safely without compromising the quality of the finished floor.