passive heating
Heat is absorbed from the environment and retained through special insulating properties.
Passive heating is a special property of a building, indicating that it has been designed to absorb and retain enough heat from its environment that it does not need any active heat generation. It does not apply to buildings without heating systems where a warm climate obviates the need for any special measures for heat retention. Passive heating is generally achieved through high-tech forms of insulation and ventilation.
The design makes environmental heat sufficient without active generation. Absorption and retention work together to maintain interior warmth.
A building needing no heating because of a warm climate has the separate no-heating meaning. Passive heating requires the special heat-retention measures described above.