Beavers make two types of lodges; bank lodges and open-water lodges. Bank lodges consist of tunnels and holes in steep-sloped banks with sticks piled over them. The more complex freestanding, open-water lodges are built over a platform of piled-up sticks. The roof is sealed up with mud apart from an air vent at the top. Both types are accessed by underwater entrances. The space inside the lodge is known as the living chamber which is above the water line. A dining area may exist near the water. North American beavers build more open-water lodges than Eurasian beavers. Beaver lodges built by first-time settlers are typically small and sloppy. More experienced families can build structures that are in diameter (above the water line) and high. One sturdy enough to withstand the coming winter can be built in just two nights.