Noise from footsteps, dropped objects, or moving furniture can easily travel through floors, disturbing the comfort of homes and workplaces. The right underscreed acoustic insulation can dramatically reduce this impact noise and create a quieter environment. But with so many options available, how do you know which product is right for your project?

This guide explains what underscreed acoustic insulation is, the key factors to consider, and how to choose the best solution for your specific needs. By the end, you’ll have a clear understanding of the products, materials, and performance standards that matter most.

What is Underscreed Acoustic Insulation?

Underscreed acoustic insulation—also known as a resilient layer—is installed beneath a screed floor to absorb and dampen sound vibrations. These vibrations are usually caused by impact noise such as footsteps, moving chairs, or objects falling to the floor.

The resilient layer works by decoupling the screed (usually a layer of concrete) from the subfloor, reducing the transfer of both airborne and impact noise. Common materials include rubber, foam, cork, and fibreglass—each chosen for their flexibility and sound-damping properties.

Building regulations such as Part E (UK) set out the minimum performance criteria for sound insulation in different building types. Choosing the correct underscreed product ensures compliance as well as improved acoustic comfort.

Key Considerations When Choosing an Underscreed Product

• Performance Metrics: Assess compression resistance, dynamic stiffness, impact sound reduction (ΔLw), and thermal conductivity.
• Flooring Type: Consider the type of finished flooring and the level of soundproofing required.
• Material & Durability: Rubber, cork, and polyurethane foam each offer different benefits.
• Compliance: Ensure the product meets international standards such as ISO 10140, EN 12354, and EN 13501-1.
• Installation Method: Proper installation is critical to long-term performance and cost-effectiveness.

Understanding Performance Metrics

To make an informed choice, it’s important to understand the main performance measurements:

• Compression Resistance: Indicates how well the material withstands pressure from foot traffic without losing effectiveness.
• Dynamic Stiffness: Lower stiffness means better vibration absorption, improving footstep noise reduction.
• Impact Sound Reduction (ΔLw): Measures how much quieter the floor becomes with the insulation. Higher values = better performance.
• Thermal Conductivity: Low thermal conductivity helps with energy efficiency, keeping spaces warmer in winter and cooler in summer.

Material Composition

Underscreed products are typically made from:

• Rubber: Excellent sound insulation, durability, and moisture resistance. Many products, such as Isolgomma’s, use high-density recycled rubber for sustainability.
• Cork: Strong thermal insulation properties, though less effective at blocking sound than rubber.
• Polyurethane Foam: Flexible and moisture-resistant, ideal for damp areas, but generally lower soundproofing performance.
• Combinations: Some products combine materials (e.g., rubber + cork) for a balance of acoustic and thermal performance.

Installation Considerations

Even the best material can fail if poorly installed. To achieve optimal results:

• Prepare the substrate—ensure it is level, clean, and dry.
• Follow manufacturer’s recommended thickness for best performance.
• Use correct seam sealing to avoid sound flanking ( Isolgomma rolls include a peel side tape for easier installation).
• Ensure compatibility with the floor structure and design.

Compliance and Standards

High-quality underscreed products should comply with strict acoustic and safety standards:

• ISO 10140: Measures airborne and impact sound insulation.
• EN 12354: Evaluates building sound insulation performance.
• EN 13501-1: Fire classification of construction products.
• VOC Certifications: Ensures products are safe and emission-free, protecting indoor air quality.

Thickness and Performance

Thicker underscreed layers usually provide better sound insulation, especially against low-frequency noise. However, balance is key—excessive thickness can be costly and difficult to install. Consider the relationship between thickness, durability, and cost to select the most efficient solution.

Environmental Considerations

Sustainability is increasingly important in construction. Rubber underscreed products stand out because they are:

• Durable: Long lifespan reduces the need for replacement.
• Recyclable: Many rubber products are fully recyclable, reducing waste.
• Energy-efficient to produce: With many manufacturers prioritising sustainable processes.

For full transparency, look for Environmental Product Declarations (EPDs) to confirm eco-friendly credentials.

Practical Applications

Residential Projects

In homes, underscreed products must balance performance, cost, and sustainability. Key factors include flooring type, sound insulation requirements, and budget. Rubber underscreed is often the preferred choice for durability and comfort.

Commercial and Public Buildings

Busy spaces like offices, restaurants, and transport hubs demand higher levels of impact noise protection. Products such as Point Impact Noise Mats and Highmat for Acoustic Floating Floors are ideal for these environments due to their strength and performance.

New Builds and Renovations

Underscreed acoustic insulation is equally effective for new constructions and retrofits. In renovations, Isolgomma underscreed systems can often be integrated without replacing the entire floor, helping projects meet modern building regulations.

Conclusion: Choosing the Right Underscreed Acoustic Product

Selecting the best underscreed acoustic insulation means weighing up performance, material composition, installation method, sustainability, and cost-effectiveness. There is no one-size-fits-all solution—every project requires a tailored approach.

At Buildtec, we supply Isolgomma underscreed acoustic solutions designed to deliver reliable, regulation-compliant sound insulation. Our team can assist with product selection, design, and specification to ensure your project achieves excellent acoustic comfort and long-term performance.