How Are Long Houses Built?

Do you mean tall buildings?

They are built by laying Iron bars which act like a basement.

In the olden days when native or ethnic people belonging to one clan in North America lived together under one roof, they built long houses. The length of the house depended on the number of families it had to house, and was typically 80 feet long hence the name.
Its design was adapted to suit the local conditions and material available.

Fire hardened poles were firmly fixed in the ground and their tops were bent over and tied to opposite side poles. This automatically gave the roofs a curved shape. Strips of bark were interwoven through the poles to make strong weatherproof walls and roof. Long houses had openings at the two ends which served as doors. Animal hides were used as coverings. There were no windows, which made the long houses very dark. But holes in the roof were made and the fires were lit directly below them to allow the smoke to escape. In winter these holes were covered and smoke would then escape through the ceiling.

The area allocated to each family was small, since the complete clan lived together as an extended family with very little privacy, but it was a matter of survival. The clan symbol would usually be placed as a totem on the front door to ward off evil. Normally the long houses are associated with the Iroquois tribe.