Noise Isolating Underlayment with Protuberances for Impact Noise Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flooring systems with rigid decorative materials like ceramic tiles and wood laminate struggle with poor acoustic properties, specifically impact noise isolation, as they fail to meet minimum IIC ratings, requiring additional support layers that increase cost and height, while prior underlayment solutions either lack sufficient dynamic stiffness or are structurally insufficient to support decorative layers.
Innovation Solution
A noise isolating underlayment with a solid resilient material featuring a bottom surface with regularly arrayed knobs or protuberances, reducing the surface area in contact with the subfloor to lower effective dynamic stiffness, thereby enhancing impact noise isolation without the need for additional structural support, and utilizing recycled rubber with a thickness between 1/64″ and 1″ to support decorative flooring.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If homogeneous underlayment layers with high void fraction or soft material are used to improve impact noise isolation, then acoustic performance improves, but the underlayment cannot support rigid topping material without cracking
Solution Approach 1:
The underlayment features localized high-density regions (protuberances) at the bottom surface for strength and contact, while maintaining overall compliance through the resilient material body. This local quality differentiation allows the underlayment to provide both noise isolation and structural support capability.
Solution Approach 2:
The underlayment combines resilient material with high-density protuberances to create a composite structure that integrates both acoustic compliance and mechanical strength functions within a single layer, eliminating the need for separate support layers.
2Strength
If additional rigid support layers are installed over soft underlayment to enable rigid flooring installation, then structural support is improved, but installed cost and overall height increase
Solution Approach 1:
The underlayment merges the functions of acoustic isolation and structural support into a single integrated layer. The protuberance structure provides both compliance for noise isolation and rigid contact points for supporting flooring materials, eliminating the need for separate support layers.
Solution Approach 2:
The underlayment modifies its effective stiffness parameter through the protuberance structure, allowing it to exhibit both compliant behavior for acoustic isolation and rigid behavior for structural support. This parameter transformation enables a single layer to fulfill multiple functional requirements.
3Object-affected harmful factors
If parallel grooves are cut into underlayment to reduce dynamic stiffness, then impact isolation improves, but grooves may align with tile edges forming fissures
Solution Approach 1:
The underlayment uses asymmetric protuberance structures that do not form continuous parallel pathways. The irregular arrangement of protuberances prevents alignment with straight tile edges, eliminating the fissure formation problem while maintaining reduced dynamic stiffness for noise isolation.
Solution Approach 2:
The protuberances feature curved or rounded geometries rather than sharp linear grooves. This curvature disrupts straight-line stress pathways and prevents the formation of continuous fissures along tile edges, while still providing the compliance needed for acoustic isolation.
4Object-affected harmful factors
If underlayment thickness is increased to improve noise isolation, then acoustic performance improves, but overall flooring system height increases
Solution Approach 1:
The underlayment concentrates its mass and stiffness properties in localized protuberances rather than uniformly distributing them. This allows thinner overall thickness while maintaining the acoustic isolation performance that would otherwise require greater thickness, as the protuberances provide focused compliance zones.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution significantly improves impact noise isolation efficiency by up to 7.3% compared to traditional systems, reduces the weight and cost of the underlayment, and minimizes the overall height of the flooring system, effectively meeting strength and acoustic performance requirements while reducing construction costs in high-rise buildings.
Implementation Method 1
a solid resilient material with a bottom surface sized to cover a given surface area... regularly arrayed knobs or protuberances whereby only a portion of the bottom surface is in contact with the subfloor... effective dynamic stiffness of the underlayment is lowered
Data Source
AI summary
A noise-reducing substrate for use in a flooring system which ha a subfloor and a floating floor upper layer. The substrate comprises a series of edge butted panels, each having a bottom surface, a top surface and side surfaces. A profile in the bottom surface of the substrate changes the substrate's effective stiffness improving the noise isolation of the substrate compared to the stiffness and noise isolation of the panel without the profile. Additionally, the profile reduces the weight of the panel, thereby reducing manufacturing and installation costs. Material hardness and profile flatness of the upper surface provide the strength and texture required to allow for installation of the floating floor layer without the need for an additional rigid backing material. Such a system greatly improves the impact noise reduction on floor/ceiling systems while keeping the installation cost low and adding little to the total system thickness.