How does CLT perform in fire?

CLT chars at a predictable rate of approximately 0.65 mm/min per exposed face. A 5-layer CLT panel (typically 160 mm) can achieve 90 minutes fire resistance with the outer lamination sacrificed to charring.

CLT chars at a predictable rate of approximately 0.65 mm/min per exposed face. A 5-layer CLT panel (typically 160 mm) can achieve 90 minutes fire resistance with the outer lamination sacrificed to charring. The cross-laminated structure prevents delamination during fire (unlike some early CLT products), maintaining structural integrity. Most building codes require CLT to be encapsulated (covered with plasterboard) in residential buildings above 2 storeys.

Why this matters

This question relates to CLT Modular Construction: How Cross-Laminated Timber Homes Are Built, 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:

→ CLT Modular Construction: How Cross-Laminated Timber Homes Are Built

Related questions

• What is CLT modular construction?
• How long does it take to erect a CLT home?
• How much does a CLT home cost compared to traditional construction?

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.