SERIOUS cold, Justen Ladda said, is when the sponge in the kitchen sink feels like wood or the toothpaste freezes or the refrigerator turns itself off, as it did one particularly frigid day last winter. Not that Mr. Ladda, a 56-year-old sculptor who has lived heat-free in his Lower East Side loft for three decades, is bothered by such extremes. “Winter comes and goes,” he’ll tell you blithely, adjusting his black wool scarf and watch cap. (Along with fingerless gloves, long underwear and felt slippers, they are part of Mr. Ladda’s at-home uniform when the mercury dips.)

Mr. Ladda, whose work is in the permanent collection of the Museum of Modern Art, decided long ago to live without central heating. Proper temperature control, you see, would require insulating his wooden ceiling, and ruining its fine acoustics. “I know this sounds really lame, but I listen to a lot of music and it just sounds better,” he said. Also, the rent on his unimproved live-work loft is only $300, well below many people’s winter utility bills.

But beyond thrift and acoustics, what is perhaps most notable about Mr. Ladda’s chilly interior is that like, say, tepee-dwelling Mongolian reindeer herders, or perhaps some very rugged environmentalists, Mr. Ladda has come to thrive in the cold.

As Americans across the country wrestle with spouses and their thermostats over how low to go — as they join contests like Freeze Yer Buns, now in its third year, a challenge posed by Deanna Duke, a Seattle-based environmental blogger who calls herself the Crunchy Chicken, to lower the thermostat to around 55 degrees, or follow the lead of the Maine couple trying to live comfortably in a furnace-free house and blogging about it in their Cold House Journal — there are those who are living nearly without heat by choice, and doing just fine, thank you very much. Indeed, 55 degrees would qualify as sauna conditions for Mr. Ladda and others whose interiors hover around the 30- or 40-degree mark in deep winter.