How to Choose the Right Thickness of Insulation for Your Van

How to Choose the Right Thickness of Insulation for Your Van

The Ultimate UK Guide for Campervan Builders & Van Conversion Projects

Insulating your van properly is one of the most important steps in any campervan conversion. But with so many insulation materials and thickness options available — 25mm? 50mm? 8mm foam? — it’s easy to feel overwhelmed.

In this guide, we’ll help you choose the right thickness of insulation for your van, depending on how you’ll use it, your climate, and the space available. Whether you're planning weekend trips, full-time van life, or winter-ready adventures, this article is packed with clear, practical tips.

Why Insulation Thickness Matters

Insulation thickness directly affects:

  • 🔥 Thermal performance (R-Value, prevents heat loss)

  • 🔇 Acoustic comfort (stops road noise and rattles)

  • 🚐 Space inside the van (you don’t want to lose too much headroom)

  • 💧 Condensation control (warmer walls = fewer damp issues)

That’s why choosing the right thickness is a balance between warmth, noise control, and space efficiency.

Recommended Insulation Thickness by Area

Van Area Recommended Thickness Ideal Material
Walls & Ceiling 25–50mm ABSoft Dacron / Hydroweld / Fleece rolls
Floor 6–12mm + top layer MLV + Foam composite, ThermoPro, FlexiLiner
Doors & Panels 5–10mm Closed-cell foam + sound deadening mat
Wheel Arches 10–20mm High-density foam or acoustic panels
Bulkhead / Cab 8–15mm ThermoPro, PeaceMAT, HeatShield layers

Step-by-Step: How to Choose the Right Thickness

1. Decide How You’ll Use Your Van

  • Full-time or winter vanlife? Go thicker (e.g. 50mm fleece + sound deadening).

  • Summer/weekends? 25mm insulation is usually enough for comfort.

2. Measure How Much Space You Can Spare

Don’t lose valuable room or head height! Choose slimline options like:

  • 8mm ThermoPro 2-in-1 Foil + Foam

  • 6mm Closed Cell Foam on floor or rear doors

  • 3mm FlexiLiner or mass-loaded vinyl where space is tight

3. Use Multiple Layers for Best Results

Rather than one thick piece, use:

  •  Butyl mat for sound deadening

  •  25mm fleece in wall cavities

  •  Foil-backed foam layer on top

This creates a thermal and acoustic system that works better than foam alone.

Product Examples by Thickness (CampervanInsulation.co.uk)

Thickness Product Name Use Case
3mm FlexiLiner MLV / 3mm Foam Door cards, tight spaces
6mm ThermoPro Adhesive Foam Composite Floor base layer, roof panels
10mm SoShield High-Density Foam Van walls, wheel arches
25mm ABSoft Dacron Acoustic Insulation Walls, ceiling, bulkheads
50mm ABSoft Thermal Fleece Roll Winter/full-time conversion

Pro Tips for Better Van Insulation

  • 🔄 Combine 2–3 materials for the best sound and heat control

  • 💧 Add a vapour barrier or reflective foil to prevent moisture build-up

  • 🛠️ Seal every gap — heat escapes faster through uninsulated areas

  • 🚫 Don’t use home loft insulation — it soaks up moisture and causes rust

FAQ: Common Questions About Van Insulation Thickness

Do I need 50mm insulation in my campervan?

Only if you’re living in the van full-time or using it in winter. For most people, 25mm (walls) + 6mm (floor) is ideal.

Is 10mm foam enough for soundproofing?

On its own, not really. Combine 10mm foam with a 2mm butyl layer or mass-loaded vinyl for proper road noise reduction.

Can insulation be too thick?

Yes — if it reduces interior space too much or traps moisture. Always balance R-value with airflow and space.

Need Help Choosing the Right Thickness?

The team at Campervan Insulation UK is here to help! Whether you're insulating a VW Transporter, Ford Transit, or Sprinter, we’ll recommend the right setup based on your van model, budget, and climate.

🛒 Browse the full collection:
https://www.campervaninsulation.co.uk/collections/all

📩 Contact us for expert advice:
https://www.campervaninsulation.co.uk/pages/contact

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