Soundproofing Concrete and Rib & Block Floors

Soundproofing your flat or multi-story home is no longer just a luxury it is a necessity for peaceful living. While concrete is excellent at blocking airborne noise (talking, music), its density makes it a primary conductor for impact noise (footsteps, dropped objects).

This guide details the best soundproofing strategies for the two most common floor types: in-situ (solid) concrete and precast rib and block systems.

1. In-Situ (Solid) Concrete Floors

Solid concrete slabs (typically 150mm–250mm thick) have high mass, which naturally blocks most voices and TV noise. However, because the material is rigid, vibrations from footsteps travel through it and radiate into the room below as sound.

Best Solutions:

• Acoustic Under-Screed Membranes: For new builds or major renovations, place a resilient membrane like D-FON or DPACT directly onto the structural slab before pouring the final screed. This "decouples" the walking surface from the building structure, reducing impact noise by up to 26 dB.

  
  

• Slimline Acoustic Mats: If you cannot lift the screed, use high-density rubber or cork-composite mats like MuteMat 2 or Novasound. These are thin (2.5mm–12mm) and can be glued directly under tiles, laminate, or parquet.

  
  

• Perimeter Flanking Strips: Always install foam edging strips around the perimeter of the room. This prevents the new floor finish from touching the walls, stopping vibrations from "flanking" (bypassing the floor and traveling down the walls).

  
  

2. Precast "Rib and Block" (Beam and Block) Floors

Rib and block floors use precast concrete beams (ribs) with hollow blocks in between, topped with a thin concrete "topping." While lighter and faster to build than in-situ slabs, they are more prone to sound issues because the hollow blocks can act like a drum, echoing and amplifying noise.

Best Solutions:

• Cavity Infill (Ceiling Side): If you have access to the ceiling below, filling the voids between the ribs with acoustic mineral wool (e.g., Rockwool) is essential. This absorbs the air-cavity resonance that causes the "drum effect".

  
  

• Floating Dry Screed Boards: On the floor side, use heavy-mass dry screed boards like SoundScreed WF28. These combine an 18mm dry screed board for mass with a wood-fibre layer for resilience, providing a solid base for hard finishes like tiles.

  
  

• Mass Loaded Vinyl (MLV) Overlay: Laying a layer of Mass Loaded Vinyl over the entire floor area adds the necessary density to block sound that would otherwise leak through the thinner precast topping.

  
  

Summary Table: Which System for Your Floor?

Feature	In-Situ Solid Concrete	Precast Rib & Block
Primary Weakness	Impact vibrations (footsteps)	Impact vibrations + Hollow resonance
Best New Build Option	Under-screed rubber membranes	Mineral wool in cavities + MLV
Best Retrofit Option	Slim rubber/cork mats	Multi-layer acoustic mats (15mm+)
Key Accessory	Perimeter flanking strips	Joint sealing for air gaps

Important Installation Tip for 2026

Regardless of the floor type, seal all air gaps. Sound is like water; it will find the smallest crack. Use acoustic sealants around pipes, electrical points, and room perimeters to ensure your soundproofing investment isn't compromised.

Explore expert guides on soundproofing solid concrete and rib-and-block floors to mitigate impact and airborne noise transmission.