What is a thermal break in curtain wall systems and why is it important?
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- Issue Time
- Aug 5,2026
A thermal break is an insulating barrier placed between the interior and exterior aluminum profiles of a curtain wall framing member. It interrupts the continuous metal path that would otherwise conduct heat between inside and outside.
**Why thermal breaks matter:**
1. **Energy efficiency:** Without a thermal break, aluminum (a highly conductive metal) transfers heat rapidly, causing energy loss. A thermal break can reduce thermal transmittance (U-value) by 50-70%, significantly lowering heating and cooling costs.
2. **Condensation prevention:** Thermal breaks keep interior aluminum surfaces warmer in cold weather, preventing condensation that can damage finishes, promote mold growth, and reduce indoor air quality.
3. **Comfort improvement:** By maintaining more stable interior surface temperatures, thermal breaks reduce cold radiation near windows, improving occupant comfort.
4. **Compliance with energy codes:** Modern building energy standards (ASHRAE 90.1, EU Directive, GB standards) increasingly require thermally-broken systems for compliance.
**How thermal breaks work:**
Typically made from polyamide (nylon) strips with glass fiber reinforcement, thermal break strips are inserted between the interior and exterior aluminum extrusions. The profiles are then mechanically joined or extruded together, creating a structural composite that maintains strength while blocking heat flow.
FOWALL integrates thermal break technology across its curtain wall, window wall, and aluminum window systems. Combined with Low-E insulating glass, FOWALL's thermally-broken systems achieve U-values suitable for the most demanding energy codes in North America, Europe, and the Middle East.