ᐅ Determining the Bathroom Floor Construction – Trial Bore Completed

Hello forum,

The bathroom on the first floor in our detached house built in 1990 is going to be renovated. We want to install a walk-in shower with a flush floor as much as possible.

Before starting, we wanted to find out whether this is feasible at all. For this purpose, I conducted a test drill and concluded the following layer structure:

I have the following questions:

• Does the floor structure seem possible or correctly determined? The "nothing" layer is probably polystyrene or something similar.
• In which layer is the drain of the existing raised shower tray likely installed — in the "nothing" layer or the concrete below?
• For a complete bathroom renovation, should the entire floor structure be removed?
• Or should the floor be left as is, only breaking out the area where the future shower will be, and otherwise installing new tiles over the existing tiles?
• Is there anything (obvious) that speaks against installing a flush-level shower?

Thanks in advance for your opinions and tips!

Werkheimer

Normally, the process should be straightforward.

First, remove the old shower.
In our case, there was just a large hole beneath the old shower.

The old shower is a surface-mounted model, approximately 17cm (7 inches) above the tiled floor.

Yes, it was the same for us.
But what good does it do to speculate? In the end, what matters is how it looks in the shower.

This is about the preliminary planning for the entire bathroom, which should not only start once the shower has been removed. Therefore, I need actual practical experience regarding typical floor build-ups—and answers to the questions above.