Floor Underlayments to Stop Footfall and Impact Noise
Acoustical floor underlayments are specifically designed to mitigate this type of noise at the source. Installed beneath finished flooring materials like hardwood, laminate, tile, vinyl, or carpet, these products serve as a resilient buffer that absorbs impact energy before it becomes airborne noise. At DDS Acoustical Specialties, we offer expert consultation on acoustical underlayments to help clients choose the right product for their project. While we do not install flooring systems ourselves, we are happy to recommend trusted flooring contractors who specialize in underlayment installation.
Acoustical underlayments are thin layers of sound-absorbing or vibration-damping material placed between subfloors and finish flooring. Their primary function is to reduce impact sound transmission—also referred to as structure-borne sound—that travels through the building structure when the floor is physically struck.
Common materials include rubber, cork, felt, foam, recycled fibers, and specialized composites. Each type has unique acoustic and mechanical properties that make it suitable for different flooring applications. For example, denser rubber underlayments may be recommended for use under ceramic tile or stone, while lightweight foam or fiber products work well beneath laminate or engineered wood.
Properly selected and installed, acoustical floor underlayments can significantly reduce impact noise without altering the appearance, comfort, or durability of the finished flooring.
Key Benefits of Acoustical Underlayments
Impact Noise Reduction: Underlayments are specifically designed to absorb and dissipate the energy from footfalls and dropped objects. By interrupting the vibration pathway between the floor and subfloor, they reduce the level of sound transmitted to rooms below. This is especially important in multi-unit residential buildings, offices, schools, and healthcare environments.
Compatibility with Flooring Types: Underlayments are available for virtually all flooring finishes, including hardwood, tile, vinyl plank, and carpet. The right underlayment will support the flooring’s performance while providing consistent acoustic protection.
Improved Comfort and Insulation: Many underlayments also provide additional benefits such as thermal insulation, moisture resistance, and cushioning for underfoot comfort. These qualities enhance the overall functionality and feel of the space.
Contributes to Code Compliance: In many commercial or residential projects, building codes or HOA requirements mandate certain sound isolation ratings such as IIC (Impact Insulation Class). Using acoustical underlayments helps meet or exceed these standards.
Simple to Integrate: Underlayments are generally easy to install as part of standard flooring procedures. Many come in rolls or panels and can be cut to fit specific layouts without requiring specialized tools.
Frequently Asked Questions
A: Impact noise is the sound generated when an object strikes a surface—like a footstep on a floor, a chair scraping, or a dropped object—that travels through the floor assembly into the structure. This form of noise differs from airborne sound, which moves through the air and is typically easier to manage with wall treatments or ceiling panels. Because impact noise transmits through the building’s structure, it's more persistent and challenging to control without specialized materials. In multi-story buildings or environments with open layouts and hard flooring surfaces, the repeated occurrence of impact noise can lead to distractions, reduced productivity, and frequent complaints from tenants or building occupants. It’s especially problematic in apartment buildings, hotels, and commercial spaces where multiple users occupy vertically stacked or adjacent rooms.
A: Acoustical floor underlayments should be used anytime you plan to install a hard surface floor in a shared or multi-level building. Whether you’re renovating a condo, outfitting an office, or building a hotel, underlayments help prevent disruptive impact noise from affecting neighboring units below. They are particularly important in spaces with high foot traffic or in buildings with rigid floor assemblies like concrete slabs or plywood subfloors, where sound tends to carry more readily. Even in new construction projects, installing the proper underlayment can help avoid costly retrofits later by ensuring compliance with building codes or sound isolation standards from the beginning.
A: Not all underlayments are created equal, and choosing the wrong one for your flooring can reduce both the lifespan of the flooring and its acoustic benefits. For example, a rigid underlayment may be ideal for tile or stone, helping to prevent cracking while also damping vibration. Conversely, engineered wood or laminate may benefit more from a resilient, compressible foam or rubber underlayment. Vinyl plank flooring often requires a thinner, denser option to maintain stability. The underlayment must complement the flooring's thickness, flexibility, and installation method. Our team at DDS Acoustical Specialties can help guide you to a solution that ensures compatibility and optimal acoustic results.
A: Acoustical floor underlayments are often rated with an IIC (Impact Insulation Class) score, which quantifies how well a floor/ceiling assembly reduces impact sound transmission. A good underlayment can improve IIC scores by 10 to 25 points or more. Practically speaking, this equates to a noticeable reduction in footstep noise, dropped item echoes, and general floor vibrations. The level of improvement depends on a variety of factors including the existing floor assembly, the quality of the underlayment, and how it’s installed. It’s important to ensure underlayments are installed properly—gaps, overlaps, or using incompatible adhesives can compromise performance.
A: Yes, acoustical underlayments do add a small amount to overall floor height, typically ranging between 2mm and 10mm. While this increase may seem minor, it can impact door clearances, transitions between different flooring types, and the alignment of cabinetry or trim. During the planning phase, it’s important to factor the added height into your architectural and design considerations. In larger commercial installations, maintaining consistent elevations across large spaces becomes essential, and underlayment specifications should be coordinated with other design elements to ensure seamless transitions.
A: Yes, many acoustical underlayments come with Class A fire ratings, ensuring they comply with fire safety codes in commercial and residential applications. This rating means the material has a low flame spread and smoke development index, making it suitable for use in both occupied spaces and high-risk environments like corridors and stairwells. Be sure to review the technical documentation and certifications for any product you specify. Our team can assist you in identifying products that not only meet acoustic targets but also adhere to local fire safety regulations.
A: Acoustical floor underlayments primarily mitigate impact sound—footsteps, objects dropping, and structural vibrations—but some types do provide limited improvement in airborne sound reduction, especially when used in concert with other acoustic systems. For example, pairing a resilient underlayment with added ceiling insulation and acoustically sealed joints can create a comprehensive barrier against both impact and airborne noise. If your project includes concerns about voices, music, or equipment noise transferring through floors, we can help recommend layered approaches for maximum sound isolation.