Question

how were the building of indus valley civilisation built

Answer 1

good drainage systems and was built with bricks that were held by tar and gypsum mortar so no water leaked. As can be seen, Mohenjo-Daro was the biggest and wealthiest city in the Indus Valley, with the most significant architectural constructions and the better sewerage systems.

Answer 2

They were brick houses and most houses had a flat roof. Some houses in poorer regions had no roof at all so they were exposed to all the weather. There was a pretty good drainage system and the pipes were made of baked clay that ran to all the houses, taking waste from bathrooms to the sewers. The sewers drained into nearby rivers.

I hope this helps you!