Can you hear your neighbours in a duplex?

Some sound always travels through a shared wall. A well built party wall reduces normal living noise to a low level. Test it before you buy.

Where is noise worst in a duplex?

Usually at shared stairs, plumbing walls and floors near the party wall. Test those spots specifically.

Can duplex soundproofing be improved after purchase?

Partly, and it is expensive. Adding insulation or a second wall layer means opening walls. It is far cheaper to buy a well built wall.

The Duplex Intensive

Duplex 101 / 10

How to Test Sound Between Duplex Units Before You Buy

By Sonia Felix, REALTOR® | byfelix.

Oakwyn Realty Downtown

The quiet showing

You stand in a duplex during a showing. Quiet. Peaceful. You picture yourself living there and it feels right.

That quiet is not information. Every showing happens in a controlled moment. Nobody is running the stairs, nobody's television is on, nobody is home on the other side. You are judging the wall on a moment that will never repeat once you live there.

What decides how much you hear

Sound between units comes down to three things.

Who built it. How carefully it was built. How the layout is arranged.

Stairs on both sides of the party wall can be a real bonus for space and flow, but only if the wall behind them was designed with proper sound separation. If it was not, you will hear every set of footsteps on those stairs for as long as you live there.

The stairs test

Bring someone with you. A partner, a friend or your REALTOR®. With permission from the seller or occupants, have them go into the other unit while you stay in this one.

Call out a name at normal volume. Run up and down the stairs. Close a door firmly. Run a tap. Listen to what comes through, and where.

If the other unit is already lived in, ask to view when the neighbours are likely home, then stay a few quiet minutes.

What is normal and what is not

It is an attached wall. Some sound will always cross it. That part is not negotiable.

How much crosses is decided by how the builder designed and built the wall, and that you can test before you write an offer. Not after you have moved in and cannot unhear it.

A second set of ears

Bring me to a showing and I will run the stairs test with you. I know the difference between normal attached wall noise and a real sound gap.

Common questions

Can you hear your neighbours in a duplex?: Some sound always travels through a shared wall. A well built party wall reduces normal living noise to a low level. Test it before you buy.
Where is noise worst in a duplex?: Usually at shared stairs, plumbing walls and floors near the party wall. Test those spots specifically.
Can duplex soundproofing be improved after purchase?: Partly, and it is expensive. Adding insulation or a second wall layer means opening walls. It is far cheaper to buy a well built wall.