Buildings and their Heat Needs

[Qatqat]

As far as I can tell....

Buildings with WORKERS need heat (steamhubs and/or heaters).
Buildings with VISITORS don't need heat.

So build your cookhouse in range of a work-time steamhub, but don't waste space in your inner rings around the generator for it if you're cramming houses (refugees, or winterhome)

All-time heat
houses, pub, guard/watch towers, medical buildings, faithkeepers, prison, propaganda

Work-time heat
workshops, child centers, cookhouses, hothouses, mines, mills, factory, field kitchens, drill

Don't need heat
fighing pit, churches, temple, shrines, gardens, squares, christmas free, archives, hunter huts, resource depots, snowpit, cemetary, beacon, outpost


DURING STORMS
During storms, when your hunters can't fly and your gardeners can't till, they still go to work and all get immediately gravely ill so either turn the buildings off, or extract all their workers when the storm hits so they stay home and warm.

Other Notes
Eventually (below -70 or so) even the steam sawmill with a steamhub and a heater won't keep your workers warm (unlike the steam coalmine or the steam steelworks or steam thumper) so be prepared for a wall drill or automaton to keep wood flowing.


The above is based only on playing and watching who gets sick, but I would love confirmation or correction if you have more information.

[Qatqat]

I don't think people get sick walking around in the cold air--only if they have to live or work in a cold location.

Some have said that if your carehouses are too far from your med tent or infirmary your people can die on the way from one to another, but that could be simply from lack of care not from walking in the cold. In any case, buiding a medical cluster with it's own dedicated steam hub seems like the right approach anyway.