Bonding of Perimeter Insulation

Key Takeaways: 

  • Use adhesive PU foams for fast, safe, and durable bonding of perimeter insulation panels, no open flame required.
  • Soudal’s expanding foam range ensures airtight, watertight, and thermally efficient insulation layers.
  • Prevents thermal bridging and maintains a continuous insulation shell around cellar and foundation walls.
  • Compatible with concrete, bitumen, and vapour barrier surfaces, suitable for PIR, PUR, and XPS insulation boards. 

Bonding of Perimeter Insulation 

When insulating cellar or foundation walls, creating a continuous, unbroken insulation layer is essential to reduce heat loss and improve overall building performance. Applying insulation externally transforms the space into an insulated but unheated zone, significantly lowering heat transfer compared to uninsulated foundations. 

Soudal’s adhesive PU foam range offers a fast and effective way to bond insulation materials directly to exterior walls without mechanical fixings or open flames. Soudafoam Flexi has a 63dB acoustic rating, it is highly flexible foam that withstands heightened movement. It is great for use around windows and doors, the flexibility means it holds it’s integrity. For smaller jobs the Soudabond 280 Aerosol is ideal, for larger-scale or professional applications, Soudabond 280 Click & Spray provides uniform adhesive coverage with minimal waste, ideal for bonding large perimeter or roof insulation panels. 

Additionally, Soudatherm Roof 330 ensures high-performance insulation bonding, particularly in roofing and horizontal applications, especially designed for energy-efficient envelope systems that demand strength and durability. Suitable insulation types include PIR, PUR, and XPS boards, with or without mineral glass fibre fleece, bitumen coatings, or aluminium lamination. For smooth XPS sheets, roughen the surface before bonding to ensure maximum adhesion. 

Products such as Pro Expanding Foam Click & Fix, Pro Expanding Foam Genius Gun, Pro Expanding Foam Aerosol and Pro Expanding Foam Gun Grade deliver excellent adhesion, fast curing, and long-term stability. However, these require support and to be held in place while they are curing, otherwise they may push parts out of alignment. 

For larger-scale or professional applications, Soudabond 280 Click & Spray provides uniform adhesive coverage with minimal waste, ideal for bonding large perimeter or roof insulation panels.  

These foams and adhesives allow for: 

  • Flame-free installation, improving on-site safety.
  • No wall perforations, preventing moisture ingress.
  • Thermal continuity, eliminating cold bridges and energy loss.
  • Versatility, adhering to concrete, bituminous substrates, and vapour barriers with sand or granule finishes. 

Suitable insulation types include PIR, PUR, and XPS boards, with or without mineral glass fibre fleece, bitumen coatings, or aluminium lamination. For smooth XPS sheets, roughen the surface before bonding to ensure maximum adhesion. 

FAQs

Why use adhesive foam instead of mechanical fixings?

It avoids wall perforations, ensuring better waterproofing and maintaining the insulation’s integrity.

Can these foams be used underground or in damp environments?

Yes, they’re formulated for use on concrete and bituminous substrates, ensuring strong adhesion and moisture resistance.

Which product is best for large-scale insulation bonding?

Soudabond 280 Click & Spray and Soudatherm Roof 330 are ideal for wide surface coverage and professional applications.

Do I need to roughen smooth insulation boards?

Yes, smooth XPS sheets should be lightly roughened to enhance bonding strength.