Armaflex, Thinsulate or cork: which van insulation actually wins?

Here's my honest take after three conversions and a pile of forum data. For a weekend warrior in temperate climates, Armaflex 19mm on panels + Thinsulate stuffed into structural ribs is the best price/performance combo I've found. Armaflex blocks vapour (μ ≥ 10000), so you don't have to design a separate vapour barrier strategy — on cold steel, that's what saves you from mould behind the skin. The chemical smell disappears in 1-2 weeks. That's really the only catch.

For full-time in serious cold (Alps, Scandinavia), I skip Thinsulate entirely and double the Armaflex: 19mm + 19mm = 38mm total, R ≈ 1.15. Vapour barrier continuity becomes non-negotiable — otherwise you get liquid water trapped between layers at -15°C outside / +18°C inside. Every seam gets Armacell aluminium tape, not some generic roll.

Acoustic-first builds: city van or daily highway? Thinsulate 42mm loft friction-fit into cavities. Its NRC 0.85 is noticeable — it's the difference between hearing your neighbour at the campground and not. You lose R if compressed, so only use it where it can keep full loft (stiffeners, ceiling between ribs).

Cork? I only recommend it for bio-sourced builds. Expect ~€2000 for an L2H2 in 10mm double-layer — expensive for 1.15 m²K/W. Great acoustics, recyclable, zero petrochemicals — but heavy (1.1-1.2 kg/m²) and absorbs moisture without a sealant. My eco compromise: 10mm cork on panels + sheep's wool in cavities.

Tight budget under €1000? Thinsulate rolls + reflective on thermal bridges only (wheel arches, crossbeams). It's a compromise but workable for mild winters.