Create one wall (really) taller than the room walls

I could happen that you need one wall really taller from the room default walls (you can define their height in the settings but it will apply to all walls) for some reasons or maybe to display something on top of it.

There is an easy way to do it even if not "obvious":
1. Create a new wall as usual ("by Edge" is easier I thought)
2. Select the wall properties
3. Click on "Partial"
4. Click on the wall height value (not the slider)
5. Enter the wall height in your unit (can be taller than the slider accepts!)

That's it!