How did Iroquois build longhouses?

Iroquois longhouses were made with different parts of the elm tree. They could be anywhere from 50 to 300 feet long, about 18 feet high, and about 20 feet wide. Their frames were made of poles of elm saplings, bent into a curved shape, forming an arched roof. These poles were tied together with ropes made from fiber from elm wood. This frame was covered with shingles made of elm bark, overlapped to keep water out. Along the top of the roof were smoke holes to let fumes from fire pits inside escape. On each end of the longhouse was a door that could be covered with an animal hide in the cold weather.  more