How to raise finish layers above the structural slab without using offsets in Revit?

[deadgameking]

Hi everyone,
I have a question about floor layer behavior and I want to clarify one requirement first:

I do not want to use vertical offsets or split the floor into separate regions/rooms.
I want this to work within a single floor type, if possible.

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Goal

I have a floor composed of:

• 300 mm structural concrete

• 80 mm ceramic finish (ı made high in purpose. not matter just example)

Total thickness = 380 mm.

What I want is:

Ceramic finish +80 mm above

Level 0.00 ──────────── Level 0.00 (reference / top of concrete)

Concrete extends 300 mm downward

So the top of the concrete slab should align with the level, and the finish should build upward above it.

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Current Problem

Revit always places the top-most layer (the finish) at the level.
So when the floor is placed at Level 0.00:

Ceramic is at 0.00 Concrete goes down to -380 mm

This is the opposite of what I want.

I tried:

• Reordering layers

• Adjusting Core Boundaries

• Changing layer Functions (Finish / Structure / Substrate)

• “Variable” layer option

But Revit still treats the finish as the top reference.

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Question

Is there any way to tell Revit:

“Use the top of the core structure as the reference plane for the floor, not the finish layer.”

[Simon_Weel]

Short answer: No.