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What Is Acoustic Underlayment?

Floor underlayments are an additional layer placed between the subfloor and the floor itself. They rest right under the carpet, tile, or wood of the floor which you walk on. Floor underlays help to reduce any minor imperfections in the subfloor for a flat and even surface, while also allowing the floor some room to expand and contract with changes in temperature and moisture. Floor underlays also help to soften the impact of footsteps and reduce noise transferred to the level below. Acoustical floor underlays are specifically designed to help reduce impact noise and are critical in the construction of apartments, offices, and any multi-story building with a lot of foot traffic.

While all floor underlays provide some noise reduction benefits, it's often not enough to completely block out the noise from above. If you've ever lived or worked in a place with thin walls where it's possible to hear the conversation next door, then you know how annoying outside noise can be and how valuable it is to have a bit of privacy. Soundproof floor underlayments are designed with noise reduction in mind. Made from polyolefin foam and rubber adhesive, these sheets reduce both impact and airborne noise, so the people a floor below won’t even know you are there.

Why Should We Care About Sound Reduction?
There are numerous reasons why sound reduction is so important. Let's say you are working in an office building with poor acoustic quality. The constant buzz of activity around you can be incredibly distracting. No one wants to hear all the foot traffic overhead from their co-workers on the top floor, chairs sliding around, or listen in on phone calls where everyone is trying to talk over each other. With so many distractions it's amazing anyone can even think! Not to mention how background noise can make it difficult to hear someone over the phone or in a meeting. Imagine how embarrassing it would be if a miscommunication led to missing a sale or messing up a client’s project, all because you couldn’t clearly hear what was being said.

Now, after a long day at the office you head home, have some dinner, and are ready to go to sleep. Unfortunately, your upstairs neighbor has decided that 3 AM is the perfect time to practice their dance routine. Maybe they have children who are full of energy and love to run around, or simply blast their favorite music or show loud enough for you to hear. Good luck getting a full night’s rest and being ready to tackle the next day with so many noisy distractions.

Noise makes it harder to focus, can lead to difficulty sleeping and impaired memory. It can negatively impact your overall mood. This is why it's so important for offices and homes to have effective noise control with soundproof underlayments built into the floors. If you are designing a new office or renovating a home, take some time to consider how noise can impact the people living and working in these spaces. A little quiet and peace of mind might be worth a whole lot to them.

How Does It Work?
Soundproof floor underlayment has a variety of helpful applications, it can be used to:
  • Reduce impact sounds
  • Dampen vibrations
  • Block airborne noise
  • Provide additional insulation
  • Provide mold resistance
You can think of underlayment like sound absorbing panels or acoustical wall fabrics, but for the floor. When an object impacts the floor, such as your shoe when taking a step, the underlayment allows for a bit of extra flexibility. The floor can bend and deform just a tiny bit, transforming the vibrational energy of being impacted into heat energy. Without underlayment, the impact would transfer directly to the studs and joists under the floor, allowing both the sound and vibration to travel to the room below. This small amount of flexibility also works to absorb airborne sounds such as when someone is talking, listening to music, or watching television. Most acoustic underlayments also provide a waterproof seal (if installed correctly) that can help keep moisture from getting under the floorboards and helps to trap in heat for additional insulation.

What Are Some Soundproof Floor Underlayment Options? When it comes to flooring there are several different options, carpet, tile, wood, and more. Each material has different qualities, and different types of underlay work best with each of them to provide the most noise reduction. WhisperMat produces several types of acoustical underlayments for all types of floors.

If you have hardwood floors, then consider WhisperMat-HW, this hardwood underlay has a ⅛” thickness to easily fit under wooden planks and boasts an IIC sound reduction rating of between 51-72. IIC stands for Impact Insulation Class, meaning how well the underlay can reduce structure-borne sounds such as walking or moving furniture. Most building codes require an IIC of at least 50. For luxury vinyl tile floors consider LVT Underlay, delivering an IIC of 50-73 depending on the floor-to-ceiling assembly in the room. We also carry sound-absorbing floor underlayment options for carpet and tile floors.

How Do You Install Floor Underlayment? After you have decided where to put your new floor underlayment and what type of flooring will go over it, it's time to get to the fun part, the installation. Installing floor underlayment is a quick and easy process that doesn’t require an entire toolbox of specialized tools. To get started you will want to make sure you have the following supplies on hand:
  • Floor Underlayment
  • Broom
  • Primer
  • Paint Roller
  • Tape Measure
  • Scissors/Utility Knife
  • Hammer Screwdriver
  • Nails and Screws
Start by removing the current floor and sweeping up any debris from the job site. Be sure to remove all the dust and tiny particles as well as the larger obstructions. You may want to dust or vacuum the flooring as well to ensure the most secure fit. Next, apply a thin coat of primer using a paint roller for an even spread. Allow the primer to dry for 20 minutes, it should become tacky to the touch. Measure and cut the underlayment to the desired length and size. You will most likely need to cut it into several strips to completely cover the floor, but other shapes may be necessary to fit around walls and doors.The peel-and-stick application of some underlayments allows for easy installation, simply remove the release paper and roll the membrane across the floor to cover the desired area. If your underlayment does not have this feature, then you may need to nail it down with a hammer and nails. Place the flooring on top, let it sit for a while, and you are done! You’ll have beautiful and quiet floors in no time!