Due to the difference in material compositions and installation, pointing out the exact STC rating of a door is hard.
However, a broad range of STC ratings can be plotted for each type of door.
| Type of Door | Approximate STC Rating |
|---|---|
| Hollow-core interior door | 20-25 |
| Solid-core interior door | 25-35 |
| Door with weatherstripping | 35-40 |
| Door with added insulation | 40-45 |
| Door with a solid core | 45-50 |
| Door with a solid core and insulation | 50-55 |
| High-performance acoustical door | 55-60 |
It’s important to note that these are approximate ratings and that actual STC ratings for a specific door depend on various factors, such as the materials used, construction, and installation.
What is a good STC rating for doors?
| STC Rating | Observed Speech Pass-through |
|---|---|
| 25 | Clear speech can be easily heard from the other side of the door |
| 30 | Loud speech is intelligible. Normal speech can be heard but not understood |
| 35 | Loud speech is audible but not clear |
| 41 | Good level of privacy. Loud speech can be heard as muffled sounds |
| 45 | Loud speech is barely audible |
| 50 | Deafening noises, such as musical instruments, can be faintly heard. |
A good STC rating for doors will depend on the specific application and the desired level of sound insulation.
In general, a higher STC rating indicates better sound insulation. A rating of 35 or higher for interior doors is generally considered good.
This means the door will block a significant amount of sound transmission, making it suitable in spaces where good isolation is essential, such as bedrooms or home offices.
An STC rating of 50 or higher for exterior doors is generally considered good. This is because exterior doors need to block more sound and be more weather tight.
This will make them suitable for use in spaces where sound isolation and weather tightness are essential such as commercial buildings or apartment buildings.
It’s important to note that other factors, such as the door’s construction, installation, and surrounding materials, can also affect its sound-blocking capabilities.
I recommend you consult an acoustic engineer before deciding on the type of door to use, especially if the sound insulation is a critical part of the project.
What is the STC rating of a wooden door?
The STC rating of a wood door can vary based on factors like the type of wood, thickness, and density of the door, as well as any added sound insulation materials.
Typically, a standard, solid wood door without additional insulation has an STC rating between 25 and 30.
If the door features a solid core, such as a solid wood or a composite body, its STC rating can be improved to around 35 or higher.
Moreover, if weatherstripping or other sound-deadening materials are integrated into the door, its STC rating can increase further.
For example, a solid wood door with insulation inside can reach an STC rating of 40-45, which is considered good for a solid wood door.
Additionally, a thicker door provides better insulation, and a tightly fitted door around the frame further increases its performance.
What is a standard STC for a door?
The STC rating of a door is not fixed, as it can vary greatly depending on the door type, materials used, and construction method.
Generally, an STC rating of 20 to 35 is considered standard for interior doors, providing good sound isolation for spaces like a home office or art room.
The standard STC rating for exterior doors is usually between 35 to 50, providing sound insulation and weather tightness.
It is important to note that the actual STC rating of a door will depend on various factors
So ask a specialist to visit and test your space before deciding on the type of door to use when soundproofing is a priority.
How does the STC rating of doors differ from windows, walls, etc.?
STC ratings are determined by measuring the sound transmission through various building elements, such as doors, windows, and walls.
For doors, the STC rating is typically determined by measuring the sound transmission through the door itself and any gaps or openings around it, such as the space between the door and the door frame.
Factors that can influence the STC rating of a door include the thickness and density of the material used, the construction of the door, and the presence of sound-deadening materials such as weatherstripping.
For windows, the STC rating is determined by measuring the sound transmission through the glass and framing materials.
Factors that can affect the STC rating of a window include the thickness and type of glass, the construction of the framing materials, and the addition of insulation or sound-deadening materials.
For walls, the STC rating is determined by measuring the sound transmission through the wall itself and any openings or gaps in the wall, such as electrical outlets or light fixtures.
Factors that can affect the STC rating of a wall include the thickness and density of the wall material, the presence of insulation, and the wall’s construction.
It is important to note that each building element will play a role in the overall sound insulation performance, and the STC rating of a door, window, or wall is only one part of the evaluation.
It is essential to consider all elements together to achieve the desired level of sound insulation.