A leaf installation, • adapted, in at least one condition, to thermally insulate two rooms (8, 9) from each other in the region of the leaf installation, and • including - a thermally insulating sliding leaf, which is disposed to be movable along a displacement path (±x) and past a counter-element (10, 20, 60), - the counter-element (10, 20, 60), which • cooperates with the leaf (60, 10) with regard to the thermal insulation of the two rooms (8, 9) from each other, as well as • is disposed to be offset with regard to the displacement path (±x) of the leaf with regard to the leaf, - at least one first sealing element (21, 30, 50, 140), which • comprises at least one first sealing section (21 a, 21b; 28; 33 - 36; 52; 53; 102), as well as • is affixed to the leaf or to the counter-element (10, 20, 60) for thermally insulating the leaf, respectively the counter-element (10, 20, 60), and - at least one second sealing element (21, 30, 50, 140), comprising at least one second sealing section (21a, 21b; 28; 33-36; 52; 53; 102), • wherein the at least one first and second sealing sections (33, 34, 52, 69) in at least one predetermined relative position of the counter-element (10, 20, 60) with regard to the leaf is configured respectively disposed in such a manner that they alone or concurrently with a respective corresponding section (7, 15, 22, 28, 35, 47, 53, 64, 101, 121, 130, 142) of the leaf and/or of the counter-element (10, 20, 60) thermally insulating enclose at least one hollow space disposed between the leaf and the counter-element (10, 20, 60) in such a manner that the hollow space during a movement of the leaf in a direction (+z) transversely to a plane of the paper of the leaf in relation to the counter-element (10, 20, 60) remains thermally insulating enclosed. • adapted, in at least one condition, to thermally insulate two rooms (8, 9) from each other in the region of the leaf installation, and • including - a thermally insulating sliding leaf, which is disposed to be movable along a displacement path (±x) and past a counter-element (10, 20, 60), - the counter-element (10, 20, 60), which • cooperates with the leaf (60, 10) with regard to the thermal insulation of the two rooms (8, 9) from each other, as well as • is disposed to be offset with regard to the displacement path (±x) of the leaf with regard to the leaf, - at least one first sealing element (21, 30, 50, 140), which • comprises at least one first sealing section (21 a, 21b; 28; 33 - 36; 52; 53; 102), as well as • is affixed to the leaf or to the counter-element (10, 20, 60) for thermally insulating the leaf, respectively the counter-element (10, 20, 60), and - at least one second sealing element (21, 30, 50, 140), comprising at least one second sealing section (21a, 21b; 28; 33-36; 52; 53; 102), - a thermally insulating sliding leaf, which is disposed to be movable along a displacement path (±x) and past a counter-element (10, 20, 60), - the counter-element (10, 20, 60), which • cooperates with the leaf (60, 10) with regard to the thermal insulation of the two rooms (8, 9) from each other, as well as • is disposed to be offset with regard to the displacement path (±x) of the leaf with regard to the leaf, • cooperates with the leaf (60, 10) with regard to the thermal insulation of the two rooms (8, 9) from each other, as well as • is disposed to be offset with regard to the displacement path (±x) of the leaf with regard to the leaf, - at least one first sealing element (21, 30, 50, 140), which • comprises at least one first sealing section (21 a, 21b; 28; 33 - 36; 52; 53; 102), as well as • is affixed to the leaf or to the counter-element (10, 20, 60) for thermally insulating the leaf, respectively the counter-element (10, 20, 60), and • comprises at least one first sealing section (21 a, 21b; 28; 33 - 36; 52; 53; 102), as well as • is affixed to the leaf or to the counter-element (10, 20, 60) for thermally insulating the leaf, respectively the counter-element (10, 20, 60), and - at least one second sealing element (21, 30, 50, 140), comprising at least one second sealing section (21a, 21b; 28; 33-36; 52; 53; 102), • wherein the at least one first and second sealing sections (33, 34, 52, 69) in at least one predetermined relative position of the counter-element (10, 20, 60) with regard to the leaf is configured respectively disposed in such a manner that they alone or concurrently with a respective corresponding section (7, 15, 22, 28, 35, 47, 53, 64, 101, 121, 130, 142) of the leaf and/or of the counter-element (10, 20, 60) thermally insulating enclose at least one hollow space disposed between the leaf and the counter-element (10, 20, 60) in such a manner that the hollow space during a movement of the leaf in a direction (+z) transversely to a plane of the paper of the leaf in relation to the counter-element (10, 20, 60) remains thermally insulating enclosed.