In the Middle Ages, heating was a labor-intensive and often inefficient process primarily dependent on open wood fires. In the early medieval period and for the peasantry, the most common source of heat was a central fire pit located in the middle of a one-room house. Smoke would drift upward and escape through small vents in the thatched roof or through the porous walls, which, while providing heat, often left the occupants smelling of woodsmoke and suffering from respiratory issues. To supplement the fire, people relied heavily on "animal heat," often building their living quarters directly adjacent to or even above the stalls where livestock were kept, utilizing the natural body heat of cows and pigs to keep the home from freezing. It wasn't until the 12th and 13th centuries that masonry fireplaces and chimneys began to appear in the homes of the elite, allowing for more controlled and smoke-free heating. For sleeping, "snuggling" was a survival tactic; multiple family members would share a single bed, buried under heavy wool blankets, featherbeds, and animal furs. In the coldest months, life was lived almost entirely around the hearth, which served as the kitchen, the social center, and the sole source of life-sustaining warmth.