Heating pipes are made of high quality polyethylene resistant to high temperatures.
Heating pipes can be laid by two systems:
Laying pipes in loose layers (sand mixed with concrete, packed ground) with a turf on it (sports field), pavers or asphalt. The thickness of all layers above pipes to cover it with the ground shall not exceed 25 cm, however, with sand covering this thickness sill not be above 20 cm.
Pipes laid in a cement mortar finished with stone plates (stairs, drives) : 6 cm of concrete mortar is required above pipes.
In case of a surface vegetation the depth of a foundation can result also from the way this surface is cared for (pipes should be embedded so it is not possible to damage them during the care steps), also in case of traffic routes the foundation depth shall be conditional on architectural and construction requirements.
As a rule under pipes there is a natural substrate or an additional granular bedding material and under it a natural base (ground). A heating system shall be filled with a heating medium, which will protect the entire installation against possible freezing; here water solutions are used.