CCF Noise Barrier vs Acoustic Foam: What's the Difference?

After sound deadening, the next layer in your vehicle soundproofing system is insulation. But should you buy CCF noise barrier or acoustic foam? They look similar but do very different things.

CCF Noise Barrier (Closed-Cell Foam)

Closed-cell foam has a sealed cell structure — air can't pass through it. This makes it a barrier that blocks airborne noise and provides thermal insulation.

Key properties:

  • Blocks airborne sound transmission
  • Excellent thermal insulation (heat and cold)
  • Water- and moisture-resistant
  • Doesn't absorb sound — it reflects and blocks it

Best for this job: self-adhesive closed-cell foam liners in 6mm to 15mm

Use for: Walls, floors and roof — anywhere you need thermal insulation as well as noise blocking.

Acoustic Foam (Open-Cell Foam)

Open-cell foam has interconnected air pockets that sound waves enter and get trapped in. It absorbs sound energy rather than blocking it.

Key properties:

  • Absorbs sound waves (especially mid- and high-frequency noise)
  • Reduces echo and reverberation
  • Lightweight and conformable
  • Not moisture-resistant — it can absorb water

Best for this job: open-cell acoustic foam sheets and bonnet liner foam

Use for: Under the bonnet, behind panels, and anywhere you want to absorb noise rather than block it.

Which Do You Need?

For Campervan and Van Conversions

CCF noise barrier is your primary insulation. You need thermal protection as well as noise blocking for walls, floor and roof. Use a 6mm or 10mm closed-cell foam liner.

For Engine Noise

Acoustic foam under the bonnet. A bonnet liner absorbs engine noise before it reaches the cabin. Use 12mm open-cell bonnet liner foam.

For Car Audio

Acoustic foam behind door cards improves speaker clarity by absorbing reflections inside the door cavity. Use 15mm open-cell acoustic foam.

For Maximum Noise Reduction

Use both. Apply CCF noise barrier as your main insulation layer, then add acoustic foam in specific areas (bonnet, behind speakers, headliner) for extra sound absorption.

The Complete Layering System

  1. Layer 1: Sound-deadening mats (on bare metal)
  2. Layer 2: CCF noise barrier (thermal insulation plus noise blocking)
  3. Layer 3: Acoustic foam (sound absorption where needed)

Shop both noise barrier and acoustic foam at Sound Proofing Shop.

Back to blog