The extruded polystyrene plate is on top.
The sequence of construction of heated floors: leveling, waterproofing, moisture-resistant membrane, extruded board, reflective film, coiled pipe (some steel mesh is in front of the coiled pipe, and some behind it the coiled pipe). coiled pipe) backfill.
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PS: The damp proof membrane is generally installed on the first floor, basement or floor in contact with the ground.
The thermal conductivity of the floor moisture-proof film is poor because common moisture-proof mats are often non-porous and covered with an air-impermeable plastic film or reflective aluminum foil.
The non-porous, moisture-resistant mat covered with an air-permeable film has poor thermal conductivity, which prevents heat from the underfloor heating below from being transmittede on the floor to warm the room. This results in a situation in which the underfloor heating remains on for a long time, but the room is not warm. At the same time, a large amount of heat from underfloor heating is trapped below, which will cause heat accumulation and the underground temperature to be too high, which has certain hidden dangers.