Abstract: The invention relates to a stadium with an arena (1) such as an ice rink, and surrounding stand (2) for spectators, and to a channel element for a channel system in the arena (1) and the surrounding stand (2). The arena (1) and the stands (2) comprise a channel system each, arranged so that air may be supplied and/or extracted for cooling or heating the arena (1) when the arena (1) is to be iced or de-iced, or so that the stands (2) may be used for heating and/or cooling of the stadium, respectively. Each channel system is made up of a number of channel elements consisting of at least three interconnected layers (3, 4, 5) of corrugated sheet material. The layers (3, 4, 5) are placed at angles in proportion to each other in such a way that corrugations of layers placed one above the other are preferably mutually perpendicular.

Abstract: The invention relates to a device by a constructional part (1) preferably extending between supporting parts (10, 11, 12) of a building or plant constructions, and preferably forming a partition between storeys, such as a floor or a deck. The constructional part (1) is self-supported, preferably of light-weight material and comprises a channel system for air, so that the constructional part (1) may provide heating and/or cooling of rooms in the building or plant construction, or may thaw snow and ice lying on the constructional part, respectively. The constructional part (1) is made up of at least three interconnected layers (2, 3, 4) of corrugated sheet material. The layers (2, 3, 4) are arranged at angles in relation to each other, in such a way that corrugations form a preferably right angle between themselves, so that the corrugations of the layers (2, 3, 4) form a channel system in the constructional part (1). A number of holes (6) are made in the intermediate layer (3).

Abstract: A grass field such as a football playing ground comprises an underground heating and heat distributing plant below the uppermost growth layer (10). In order to provide a grass field built up, layer on layer, and heatable from below, as well as exhibiting a structure which will not be able to settle in the course of time, and wherein the pitch-corer substantially maintains its flat, plane, essentially horizontal original condition, the grass field is based on the use of air-carried heat energy, heated air being brought to distribute itself in a lower hot air distributing cavity layer covering the basal area of the pitch, and wherein some heat energy of the supplied air is liberated to wall faces (4, 5) defining said lower cavity layer, whereafter return air within an upper cavity layer assigned air communication holes (5′) in a partition wall can be drawn off for reheating and reuse.