Session · Enclosures · Designers and consultants · Builders and trades

Foam Free High Performance Building Enclosures

Nick Shaw · March 19, 2026 · Chapter · PHDC (Passive House DC)

A practical guide to high-performance building enclosures without foam: why foam insulation is seen as hindering air, vapor, and thermal control, health, and sustainability goals, and how practitioners build without it.

Key points

• What sets high-performance enclosures apart, and how that is changing.
• Practitioners' concerns about foam insulation.
• How a foam-free enclosure can meet high-performance goals.
• Practical methods for building a foam-free high-performance enclosure.

Learning objectives

• Define what qualities differentiate high-performance enclosures from typical construction and how those qualities are evolving.
• Describe practitioner concerns of foam insulation hindering efforts to meet the evolving high-performance qualities.
• Describe how a foam free enclosure can more robustly achieve the qualities of high-performance.
• Describe practical methodologies practitioners can implement, to successfully produce a high-performance enclosure that is foam free.

Topics: Embodied carbon, Insulation and assemblies