We LOVE the Poly-Dome calf huts. Very portable as well.We're in Wisconsin (can get VERY cold) and have always used calf hutches for our goaties. Our favorite brand is the Poly Dome round hutches, believe they are about 7.5' in diameter and about 4.5' high in the center. VERY durable, even when the wind took one. They heat up nice during the sunny days and are small enough they retain a bit of heat during the cold nights.