Are Apartments Soundproof?

A few things can compromise an otherwise great apartment more than noise filtering into your interior space. Footsteps from the apartment above, hooting cars, shuffling feet in the corridors, and other types of noise can be quite annoying, and the only way to avoid them is choosing a soundproof apartment when house hunting. There is one problem, though.


Not all apartments are soundproof even though the International Building Code has set the minimum noise control requirements. To find out if an apartment is soundproof, consider the type of walls separating the units, the type of windows and flooring, and the type of ceiling construction.


In the rest of this post, we’ll explore in detail why not all apartments are soundproof despite the Building Code stipulations and provide some helpful tips for determining whether an apartment is soundproof. Let’s get started, shall we?

Building Code Requirements for Noise Control in an Apartment

The International Building Code (IBC) is pretty much the standard for building construction in most jurisdictions in America. Adopted in the US in 2018, it provides the minimum standards that residential buildings must conform to, and among these noise control requirements. 


The IBC’s minimum requirements for noise control in apartments and other residential units are 50 STC and 50 IIC.


But while some building inspection departments mandate field-testing before an occupancy certificate is issued, most don’t. Rather, they rely on the architect’s acoustic design recommendations to meet the Building Code minimum noise control requirements in apartments.


Unfortunately for the renter, the architect’s recommendations are sometimes not reflected in what’s actually built, and that’s why some apartments may not be soundproof even though the blueprint and building specifications might suggest otherwise.

Factors to Consider to Determine if the Apartment Is Soundproof

Besides having another person make noise in the apartment above, below, or adjacent space, there are several factors you can consider to determine whether the apartment you’re eyeing is soundproof.


Let’s review each!

The Type of Walls Separating the Units

The type of walls separating your apartment from adjacent units will determine how noise from your next-door neighbor will make it into your space. And by type of wall, we mean the kind of materials used and the characteristics of the construction.


For material, you’ll want concrete or plaster walls, because these are great for blocking out external sounds. That’s because their thickness and surface solidity allow them to reflect away noise, preventing most of the sound energy from traveling through. 


The keyword here is most, because a little sound energy may make it through without the right type of construction, which brings us to the next point in our discussion: the characteristics of the construction.


Mass is the first thing you’ll want to check as far as the characteristics of the wall construction are concerned. For effective sound control, the apartment’s walls should have so much mass that when you hit any of them hard with the palm of your hand, it doesn’t vibrate. Generally, the more the wall vibrates when you hit it, the more low-frequency noise (such as bass from your neighbor’s subwoofer) you’ll experience.


In addition to the right mass, you’ll also want the wall construction to have at least one of the following sound control elements:


  • Be decoupled
  • Have an extra layer of drywall
  • Feature resilient channels
  • Be sound-treated with acoustic sealants and soundproofing compounds


To check if a wall between two adjacent apartments was constructed with an emphasis on soundproofing, knock on the walls to find out if they’re hollow or filled with fiberglass. 


Alternatively, remove a wall plate from one of the switches in the wall and see if you can spot fiberglass in the cavity around the backbox’s edges. While you’re at it, see if there are two layers of drywall between the backbox and the plate. If so, chances are the apartment is soundproof.

The Type of Windows

Windows greatly affect the sound control characteristics of an apartment because they act as gaps in the exterior walls for sound to penetrate. Without the right kind, noise from outside sources such as hooting cars will easily find its way into your interior space even if your walls are soundproof.


To find out if the windows of the apartment you’re eyeing are soundproof, check if they’re single, double, or triple pane. While triple pane windows are the best for sound control, they’re quite expensive, and apartments with such windows are very rare. As such, you’ll likely find single or double pane windows in most apartments, and you’ll want to go with the latter for the best noise control.

Type of Flooring

The type of flooring determines how much impact noise you hear from your downstairs neighbor. And if all floors in the whole apartment complex are the same, the flooring type will also dictate how much of your upstairs neighbor’s footsteps you’ll hear.


If the floor in the apartment you’re eyeing is hard (as opposed to carpet), you’ll want to ensure that it’s glued and not nailed because nails transmit sound. More importantly, it should be fitted with flooring underlayment. 


In simple terms, this refers to a thin layer of cushioning that’s usually installed between the subfloor and a carpet or hardwood floor. It can be made of rubber, plastic, or foam, and is usually installed to insulate interior spaces against not only sound but also heat and moisture.


In addition to the nature of the construction, the type of materials making up the floor also determines its ability to block out impact noise. Generally, carpets are much quieter than ceramic and hardwood floors unless the latter two are well isolated.

The Ceiling Construction

The way the ceiling is constructed and the materials used also affect an apartment’s sound control properties. That’s because, in an apartment complex, the ceiling is what separates you from your upstairs neighbor. So if it wasn’t constructed with soundproofing in mind, you’d likely experience impact and airborne noise from upstairs. 


To find out if the ceiling in your prospective apartment is soundproof, check if it has any of the following sound control elements: 

A Dropped Ceiling

A dropped ceiling will look like a secondary ceiling suspended from the unit’s standard structural ceiling. In soundproofing, this kind of installation is used to create space between the standard ceiling and your interior space (think having two layers of the ceiling with space between them). By doing so, it breaks the path of sound vibrations from upstairs, which helps protect your interior space against impact and airborne noise.

Soundproof Drywall

Soundproof drywall isn’t to be confused with standard drywall even though both are made of gypsum. The former is usually around ⅝ inches (1.5875 cm) thick, which is slightly thicker than the ½-inch (1.27 cm) thickness of standard drywall. That extra bit of thickness is partly what makes soundproof drywall better for sound control because it limits how much it vibrates when faced with soundwaves.


While it might not be possible when inspecting a prospective apartment, you can also differentiate soundproof drywall from standard drywall by examining the composition. 


Typically, traditional drywall comprises a layer of mineral gypsum pressed between layers of paper. While soundproof drywall panels do have gypsum, it’s usually alternated with layers of plastic polymers or glue. Depending on the brand, these layers may also include metals and/or ceramics to further stiffen the drywall, so it doesn’t vibrate.

Acoustic Foam or Tiles

Acoustic foam or tiles are easier to spot in an apartment ceiling, provided you have an idea of what they look like. 


Typically acoustic tiles are made of fiberglass, and higher-end options may feature a layer of sound-interruption foil. You’ll likely find them fitted on dropped or drywall ceilings, held in place by a metal grid or specialized clips, respectively. On the other hand, acoustic foam looks pretty much like an egg tray and is used the same way as acoustic tiles.

Fiberglass Insulation

Last on the list of soundproofing elements to look for in a ceiling is fiberglass insulation. You’ll typically find it in fiberglass ceilings, where it’ll be sandwiched between an apartment’s existing subfloor and a layer of drywall.

The Bottom Line

Ultimately, not all apartments are soundproof despite the current Building Code, and their capability in this regard varies according to the factors we’ve reviewed in this post. Hopefully, you’ll be able to find a soundproof unit by keeping those considerations in mind when apartment hunting. Best of luck!