Cold rooms

[Alluvium]

Historically, a lot of towns and villages had community cooling houses and ice houses, to help store food. These were often built underground to provide good thermal insulation, and would be loaded with large blocks of ice in winter to help food stay cold into the warmer months.

I wonder if some mechanic could be implemented for building a "cold room", similar to a cellar. These would have to be underground, lined with thermally insulating walls, and sealed with a heavy door (perhaps a metal or slate door).

Ice could be harvested only in nothern climates in the winter when lakes and ponds freeze over. Traditionally ice was cut using a saw, so perhaps sawing the blocks around an ice block would drop it intact, similar to how stone blocks are obtained. Once in a cold room, the ice would melt slowly to water, depending on the thermal insulation of the room. Any heat generating activities in the room (firepits, furnaces etc) would increase the melt rate.

The cold room would give an extra preservation bonus for certain stored foods (vegetables, meat, meals) but perhaps be detrimental for storage of items like grain due to the damp conditions? Also, cold rooms would be unsuitable for maturing / ripening of cheese etc. due to being too cold. This would ensure they were not a simple upgrade to a cellar but rather a different room type with different function. 

Edited September 17 by Alluvium
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