What is the best insulation for a timber frame house?

The optimal insulation depends on performance priorities. For moisture safety and breathability, wood fibre insulation is the gold standard — it is hygroscopic (absorbs and releases moisture without damage), vapour-permeable, and provides excellent summer overheating protection due to high thermal mass.

The optimal insulation depends on performance priorities. For moisture safety and breathability, wood fibre insulation is the gold standard — it is hygroscopic (absorbs and releases moisture without damage), vapour-permeable, and provides excellent summer overheating protection due to high thermal mass. For cost-effectiveness, mineral wool remains the industry standard with proven performance. For minimum wall thickness, PIR/PUR rigid foam achieves the lowest U-values in the thinnest build-up. For sustainability, cellulose (recycled newspaper) offers excellent thermal performance with the lowest embodied carbon of any insulation material.

Why this matters

This question relates to Insulation for Timber Frame Homes: Materials & Performance Comparison, which covers the broader topic in detail. Understanding this specific aspect helps architects, builders, and timber dealers make informed specification decisions.

For full context and additional technical detail, see our comprehensive guide:

→ Insulation for Timber Frame Homes: Materials & Performance Comparison

Related questions

• What U-value should a timber frame wall achieve?
• Should timber frame insulation be breathable?
• Can I use PIR insulation in a timber frame?

About this answer

This answer is part of the PuurModulair Knowledge Base — comprehensive timber specification guidance for architects, builders, and dealers across the UK, EU, and Scandinavia.