Party wall

A party wall is a wall that is shared by two people, or present between a room inside a building or a house and an adjoining room or building. It usually divides an apartment into two parts. Party walls are usually made of brick, concrete or wood and are designed to keep the apartments separate and soundproof. The people living in the apartments each own half of the wall, and if one of them wants to make a change to it, they need permission from the other.