Why does larch weather unevenly?

Uneven weathering occurs because different parts of a facade receive different levels of UV exposure and moisture. South-facing areas weather fastest (silver within 12–18 months), while sheltered areas under overhangs remain golden-brown for years.

Uneven weathering occurs because different parts of a facade receive different levels of UV exposure and moisture. South-facing areas weather fastest (silver within 12–18 months), while sheltered areas under overhangs remain golden-brown for years. Rain washing removes surface deposits from exposed areas while sheltered zones accumulate tannin staining. Solutions include: pre-weathering treatments, consistent detailing to ensure uniform exposure, or accepting the variation as a natural characteristic.

Why this matters

This question relates to European Larch: Natural Durability, Cladding & Structural Applications, 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:

→ European Larch: Natural Durability, Cladding & Structural Applications

Related questions

• What durability class is European Larch?
• How long does larch cladding last without treatment?
• What is the difference between Siberian Larch and European Larch?

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.