Uncoupling mat with heating elements

An uncoupling mat (1) comprising:

• a flexible plastic layer (2) made of plastic film with structuring that defines indentations (6) provided with undercuts (5) on a first, top side (4) and cavities (8) positioned between the indentations (6) on an opposite second, bottom side (7), and
• a fleece or fabric (3) securely connected to the bottom side (7) and covering the cavities (8),
• wherein:
• a cross-section of the indentations (6) in at least some corner regions (10) increases constantly from the bottom side (7) toward the top side (4);
• and
• a cross-section of the indentations (6) in center portions of the walls of the indentations beneath the undercuts remains substantially constant, extending vertically straight from the bottom side (7) to the top side (4).

A slab covering installation, comprising:

• a substrate (14);
• an uncoupling mat (1) fastened to the substrate (14) with a thin bed mortar (16), the uncoupling mat (1) comprising:
• a flexible plastic layer (2) made of plastic film with structuring that defines indentations (6) provided with undercuts (5) on a first, top side (4) and cavities (8) positioned between the indentations (6) on an opposite second, bottom side (7), and
• a fleece or fabric (3) securely connected to the bottom side (7) and covering the cavities (8),
• wherein:
• a cross-section of the indentations (6) in at least some corner regions (10) increases from the bottom side (7) toward the top side (4);
• a thin bed mortar (16) installed atop the uncoupling mat such that the thin bed mortar substantially fills the indentations (6) beneath the undercuts (5);
• and
• a slab covering (15) fastened to the thin bed mortar atop the uncoupling mat.