ᐅ Floor construction and waterproofing for exterior entrance areas

Hello,

I have an entrance area where the front door is recessed into the house. That means I have about 2 x 1 meters (6.5 x 3.3 feet) outside, which is covered but already the basement ceiling. Currently, it is a raw concrete slab with a waterproof membrane on top. This outdoor area is 16.5 cm (6.5 inches) below the aluminum door frame, and it is going to receive a 3 cm (1.2 inches) granite slab as flooring. The side walls of the entrance are plastered, with wood fiber insulation behind them.

I want to waterproof the entrance area and also create a professional floor build-up for the granite slab that won’t settle over time. The floor structure should be insulated to prevent condensation on the basement ceiling.

How is this typically done nowadays, and what materials or methods are recommended?

I would glue XPS boards with a bitumen thick coating onto the concrete slab. Then, on top of a layer of pozzolan cement mortar, the granite slab is installed. We used this method for all floor-to-ceiling windows.

Advantages:
- Insulation is provided
- No settling possible
- XPS is non-capillary and does not transport moisture

This is how it looked during installation.

[ATTACH alt="bodenaufbau-und-abdichtung-fuer-eingang-im-aussenbereich-687191-1.jpeg"]91257[/ATTACH]
[ATTACH alt="bodenaufbau-und-abdichtung-fuer-eingang-im-aussenbereich-687191-2.jpeg"]91258[/ATTACH]
[ATTACH alt="bodenaufbau-und-abdichtung-fuer-eingang-im-aussenbereich-687191-3.jpeg"]91259[/ATTACH]
[ATTACH width="351px" alt="bodenaufbau-und-abdichtung-fuer-eingang-im-aussenbereich-687191-4.jpeg"]91260[/ATTACH]