What is a Demising Wall?

Definition: A demising wall is a wall that separates two adjacent tenants or a tenant from one of the building’s common areas. It divides two separate real estate entities from each other.

What Does Demising Wall Mean?

Demising walls are structural divisions built to establish a physical separation between adjacent properties. The purpose of the wall itself is the same in every case but the wall can be used in different scenarios. For example, in an apartment building with many units, each unit is separated from the other (and from adjacent common areas) by demising walls. The wall establishes the limits between one property and the other.

In the case of common areas, the wall separates the apartment’s property from the building’s property. Depending on the real estate construction legislation of each country or state, demising walls can be made of different materials. They normally aim to reduce noise and sometimes they are equipped with fire protection. On the other hand, they sometimes serve as a structural wall for the building.

In other cases, demising walls can be constructed when a scenario of conflict arises between two owners that were previously partners. These owners may decide to build a demising wall to separate the property in two identical sides, in order to be apart from each other.


Let’s say the owners of an apartment building have been receiving some complaints from the current tenants about excessive noise transfer between apartments. The tenants living in apartment 1B complained they can hear their tenant’s TV through one of their apartment walls, even when the volume is low.

These tenants asked the owners to reinforce the demising walls of their apartments. After several unanswered notifications they decided to file a complaint with the city’s real estate authority and asked for an inspection to analyze noise levels and see if they comply with the minimum standards established by the city ordinances.

The inspection revealed that the noise level was higher than the standard. That means the building owners must reinforce each of the building’s demising wall where this situation is happening with noise-reducing material.