How do you achieve airtightness in a timber Passive House?

Airtightness in timber construction is achieved through a continuous airtight layer — typically an OSB or plywood board on the warm side of the insulation, with all joints taped using specialist airtightness tape. Alternatively, a dedicated airtight membrane (e.g.

Airtightness in timber construction is achieved through a continuous airtight layer — typically an OSB or plywood board on the warm side of the insulation, with all joints taped using specialist airtightness tape. Alternatively, a dedicated airtight membrane (e.g. pro clima Intello) can be used. The critical requirement is continuity — every junction, penetration, and service entry must be sealed. The Passive House standard requires n50 ≤ 0.6 ACH (air changes per hour at 50 Pa pressure difference).

Why this matters

This question relates to Passive House Timber Construction: Achieving U-Values Below 0.15, 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:

→ Passive House Timber Construction: Achieving U-Values Below 0.15

Related questions

• Can you build a Passive House with timber frame?
• What U-value is required for Passive House walls?
• How thick does a Passive House timber wall need to be?

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.