Terrac® Acoustic Rubber Underlay - Various Thicknesses

Terrac® Prime Acoustic Rubber Underlay | Recycled SBR Rubber | 3mm / 5mm / 6mm / 10mm

Terrac® Prime is a rubber granulate underlay manufactured from recycled SBR rubber particles bonded with a cold cure polyurethane elastomer. The granulate construction — dense rubber particles held in a resilient PuR matrix — gives the product its acoustic performance: the granular structure compresses under load and absorbs impact energy before it can be transmitted into the floor assembly below, while the mass and density of the rubber layer provides resistance to airborne sound transmission through the floor.

At 750kg/m³, Terrac® Prime is a high-density product relative to foam and cork underlays of equivalent thickness, and maintains its resilience under sustained compressive loads without the settlement or compression set so performance is maintained over time. 

Four thickness options are available — 3mm, 5mm, 6mm, and 10mm — each supplied on rolls of different dimensions to reflect the weight and coverage appropriate to that thickness. Thickness selection is determined by the floor covering type, the subfloor condition, the acoustic performance required by the specification, and the available floor build-up depth.

Applications

• Laminate and engineered timber floors — Terrac® Prime provides the resilient, load-bearing underlay required beneath floating floor systems while delivering significantly higher impact sound reduction than standard foam underlays. The high density and compressive strength support the floor structure under furniture and point loads without the long-term compression set that causes hollow spots and creak under foam underlays. 3mm and 5mm are the standard specifications beneath floating floors where build-up depth is limited.
• Stone, ceramic tile, and concrete overlays — the granulate construction is compatible with tile adhesive and thin-bed screed systems, providing a resilient intermediate layer that reduces impact transmission through hard floor finishes. Terrac® Prime is designed to prevent screed cracking by absorbing differential movement and impact stress — 6mm and 10mm are typically specified in this application.
• Vinyl and LVT — suitable as a high-performance acoustic base for glue-down and loose-lay vinyl and LVT installations where impact noise reduction is required beyond what a foam or felt underlay provides.
• Gym and fitness floors — the primary application for the 10mm version. Under rubber gym tiles, hardwood sprung floors, and laminate in fitness studios, commercial gyms, and home workout spaces, Terrac® Prime absorbs the shock and vibration generated by dropped weights, cardio equipment, and high-impact exercise. The rubber-to-rubber compatibility between Terrac® Prime and rubber gym tiles ensures full contact bonding without adhesive incompatibility issues.
• Underfloor heating systems — compatible with underfloor heating. The material maintains its dimensional stability and resilience through the thermal cycling of wet and electric underfloor heating systems.

Product Benefits

• Recycled SBR rubber — 750kg/m³ density. Manufactured from recycled styrene-butadiene rubber granulate, Terrac® Prime converts post-industrial rubber waste into a high-density acoustic underlay. At 750kg/m³, it is significantly denser than foam or cork underlays of equivalent thickness, providing greater resistance to sound transmission and impact energy absorption.
• Granulate construction — resilience under sustained load. The PuR-bonded rubber granulate structure maintains its resilience and acoustic performance under the sustained compressive loads of furniture, fixtures, and heavy equipment. Unlike foam underlays, which compress permanently under point loads and lose acoustic performance in high-traffic areas, the granulate matrix recovers after loading.
• Four thickness options — 3mm to 10mm. The range covers standard floating floor installations at 3mm and 5mm, tile and screed applications at 6mm, and high-impact gym and heavy-use commercial applications at 10mm. Each thickness is supplied on a roll sized for the weight and coverage appropriate to that specification.
• Slip resistance — Class X wet, Class F dry. Tested and classified for slip resistance under both wet and dry pendulum conditions, confirming safe handling and positioning during installation before the floor covering is laid.
• Prevents screed cracking. The resilience of the granulate layer absorbs differential movement and impact stress within screed and tile systems, reducing the risk of surface cracking in hard floor finishes over time.
• Dimensionally stable — DIN 7715 Class M4. Dimensional tolerance of 1.5% ensures consistent thickness across the roll, which is critical for floating floor installations where variation in underlay thickness causes unevenness and instability in the floor covering above.

Installation

Unroll Terrac® Prime and allow to acclimatise to room temperature before installation — cold rubber is less flexible and harder to lay flat. Cut to size using a sharp knife and straightedge. Butt all joins tightly with no gaps or overlaps. For floating floor installations, secure joins with tape to prevent movement during the floor covering installation. For tile and screed applications, confirm compatibility of the tile adhesive or screed system with the rubber substrate before proceeding. The subfloor should be clean, level, and structurally sound — surface irregularities telegraph through the underlay and into the floor covering above.

The Technical Details