How do you soundproof a condo or townhouse floor? It may seem like an impossible task. It’s true that it’s not something you can wing or make up as you go along. A sound strategy (pun intended) is a must. Why do it?
Soundproofing under hardwood floors and other surfaces can make an incredible difference in quality of life. You’ll feel like your space is more private, it will be easier to relax, entertainment won’t interrupt people from floor to floor. Most importantly, it will be much easier to get to sleep. It also makes your properties easier to rent, lease, or sell: no one wants to hear the neighbors footsteps all night!
Origin and Type of Sound
How do we start? Let’s figure out the problem first. What kind of noise is bothering you about your condo or townhouse? There are two lines of questions to ask here:
- Origination: Where is the noise coming from? Is it traveling from a higher floor to a lower floor, or from a lower floor to a higher floor?
- Sound: Does the problem come from impacts or does it travel through the air?
Soundproofing under hardwood floors works best to dampen impact noises: these are things like footsteps and stomps, furniture being moved, and items being dropped. Sound that isn’t in direct contact with the floor can make it vibrate and still travel through – lower sounds travel through solid material more easily. This is why, when you hear music from another room, is sounds deeper than if you were in the same room listening to it.
You can easily tell the difference soundproofing will make. Have someone go to the floor above and walk, stomp, and talk at different volumes. The more impact noises you hear, the more you need soundproofing. If you can hear voices carry, but can’t hear the stomps, this is sound traveling through the air and it may simply be a matter of having an open floor plan where sounds carry. Soundproofing will help most with impact noises and noises that are so loud they carry through the floor. It will help, but not as much, with noises that carry through the air.
Basic Soundproofing
The easiest approach to soundproofing is to invest in a carpet and pad. Both should be thick. Here, the pad is doing most of the work in sound mitigation. The carpet is mostly there for the aesthetic and design qualities.
There are obvious disadvantages to this. You can no longer see your hardwood floor under the carpet. Carpets are tougher to clean and many can trap allergens and microbes. Allergy-sufferers don’t always do well with carpets.
Furthermore, a carpet can work well for impact noises, but not as effectively for loud noises that vibrate through the floor. Music, TV, video games, exercise equipment, shouting…these start as airborne noises but can be so loud they vibrate through the floor. If you have a nice entertainment system, the subwoofer is almost always located near the floor. This complicates matters, and carpet won’t deter most of these sounds from reaching the floor below. Carpet negates impact noises, but not these other sounds.
Soundproofing Under Hardwood Floors in a Condo or Townhouse
In this case, it’s more effective to install a damping compound and a resilient underlayment. This allows you to keep the beauty of your hardwood, and takes care of more than just impact noises. You’ll also have more control over the type of sounds your floor is best at eliminating.
A resilient underlayment acts much like the pad under a carpet does, except it can be more effective in many ways. An underlayment might be made of shredded rubber, regular rubber, foam, fiber, or cork. A heavier underlayment is actually an advantage. The more mass an underlayment has, the more soundproofing it provides. This is because it absorbs the sound – the sound has more mass to vibrate through before coming out the other side (the floor below).
A damping compound is a soundproofing compound that’s simply applied over the subfloor. It’s above the subfloor, but underneath the underlayment. This is essentially a soundproofing material. The most important thing is that the damping compound is secured between two other solid, inflexible surfaces. This means the compound itself won’t carry the sound. Extra layers of damping compound can be added to provide even more soundproofing.
The floor on top of the underlayment and damping compound should be floating rather than secured. It shouldn’t be secured to the layers underneath it by screws, nails, or any other fashion. This avoids impacts on the floor transferring to the layers underneath.
Extra Steps Make a Big Difference
Now if you think about it, if impacts on the floor can transfer to layers underneath and we leave the floor floating because of this…what about walls? If the floor touches walls, won’t it just transfer noise vibrations to the walls and carry down this way? That’s a smart question, and the answer is yes.
To solve this, acoustic sealant can be used in the gap between the floor edge and wall. This assists in hardwood’s natural expansion and contraction as temperatures and humidity change, and it also creates a soundproof barrier that limits noise transferring from floor to wall.
Noise should always be addressed close to its source. Soundproof the floor where the noise is being caused. If noise is carrying up from the first floor, soundproofing the second floor won’t be as efficient as soundproofing solutions on your first floor.
If you have tile floors and the noise you’re dealing with is echoes, you may need to look at soundproofing the walls.
Depending on the type of noise you’re dealing with, there are a number of adjustments in materials and installation techniques that can make incredible differences. If you’re putting a new subfloor in, there are even ways to construct it to reduce noise propagation.
Consult a condo flooring contractor with experience in soundproofing condo or townhouse floors. It’s the extra details that come from experience that can make the biggest difference in creating a restful, relaxing, private space.
