Thermal Break Aluminium Frames Singapore | EZZO.SG Guide

Home › Blog › Thermal Break Aluminium Frames Glass Technology · 9 April 2026 · 6 min read Why Thermal Break Aluminium Frames Are Essential for Singapore's Climate Aluminium is one of the best thermal conductors on the planet — a quality that makes it ideal for aircraft and heat sinks, but deeply problematic in a window frame. In Singapore's 32 °C, 85% humidity environment, a standard aluminium frame quietly works against your air-conditioning around the clock. A thermal break changes that equation entirely. Put your palm against an aluminium window frame on a typical Singapore afternoon. If the frame feels warm — or even hot — to the touch, that is not just discomfort. It is a physical measurement of energy flowing directly from the tropical heat outside into your air-conditioned interior. Every joule of heat the frame transfers is a joule your aircon must remove. Over a Singapore year, that adds up. This is the thermal bridge problem , and it is the single most important factor separating a standard aluminium window from a high-performance one. Understanding it — and the solution, a thermal break — will change how you evaluate every window specification you read. The Thermal Bridge Problem in Standard Aluminium Frames Aluminium has a thermal conductivity of approximately 205 W/m·K. Glass, by comparison, conducts heat at roughly 1 W/m·K. This means aluminium conducts heat approximately 200 times more readily than glass , and over 1,000 times more readily than still air. In a standard, non-thermally-broken frame, the outer aluminium section (exposed to 32–34 °C ambient heat and direct solar radiation that can push surface temperatures above 60 °C) is physically connected — as one continuous piece of metal — to the inner aluminium section inside your cooled room. Heat does what physics demands: it flows from hot to cold, and it will take the path of least resistance. In a standard aluminium window, the frame itself is that path. The aluminium becomes what engineers call a thermal bridge — a direct, high-conductivity channel bypassing any insulation you might have in your walls or in the glazing. Your double-glazed glass unit can have an argon-filled cavity and Low-E coating performing beautifully, while the frame around it silently undoes a significant portion of that work. The numbers in context: In a climate like Singapore's, where exterior temperatures exceed interior temperatures by 10–14 °C for much of the day, a thermally unbroken aluminium frame with U-value around 5–7 W/m²K can account for a disproportionate share of total window heat gain — even in a double-glazed system — because the frame area, while smaller than the glass area, conducts heat so much faster per unit area. What Is a Thermal Break and How Does It Work? A thermal break is a continuous strip of low-conductivity material inserted into the aluminium extrusion, physically separating the outer aluminium section from the inner aluminium section . The two halves of the frame are mechanically locked together but thermally isolated: heat attempting to travel through the frame must pass through this insulating strip, which it does very slowly. The result is a frame that behaves like two separate aluminium structures joined by a poor conductor. The outer section gets hot in Singapore sun. The inner section stays cool, closely matching the temperature of the interior air. The thermal bridge is broken. This sounds simple, but the engineering is demanding. The strip must be: Thermally resistive enough to provide meaningful insulation across the range of Singapore conditions Mechanically strong enough to handle the structural loads of a large window or door sash — including wind pressure, operating cycles, and the weight of glass units that may exceed 50 kg per panel Dimensionally stable across temperature swings from sub-20 °C (conditioned interior) to 70+ °C (exterior surface in direct sun) Resistant to UV, moisture, and the chemical environment of coastal Singapore PA66 Nylon — Why This Material Is the Industry Standard The material that meets all these requirements is PA66 Nylon (Polyamide 66) , and it has become the global industry standard for thermal break strips in aluminium window and door systems. Its properties make it uniquely suited to the task: 0.25 W/m·K thermal conductivity — vs 205 for aluminium 260 °C Melting point — stable at Singapore surface temperatures 80+ MPa Tensile strength — handles structural window loads 50+ yr Service life expectancy in typical installations PA66's thermal conductivity of approximately 0.25 W/m·K is around 820 times lower than aluminium. A 24 mm wide PA66 strip therefore provides thermal resistance roughly equivalent to a 5-metre thick aluminium section — without adding bulk to the frame. The strip is typically glass-fibre reinforced to enhance stiffness, ensuring the two aluminium halves remain aligned under load without any flex that would compromise weathersealing. PA66 also has excellent resistance to the chemicals found in sealants, lubricants, and cleaning agents, and its dimensional change across the temperature range seen in Singapore installations is low and predictable — critical for maintaining the airtight seals that govern acoustic and thermal performance. Inferior thermal break materials — including polyurethane foams, some PVC variants, and rubber strips — are used in budget systems. They compromise on one or more of these properties: foams degrade under structural load, some PVC grades creep over time, and rubber strips may not maintain the dimensional stability needed for multi-decade performance. PA66 Nylon is the specification to look for. The Complete System: Thermal Break Frame + IGU Together A thermal break frame does not operate in isolation. In a high-performance window system, it works in conjunction with an Insulated Glass Unit (IGU) — typically a double-glazed assembly — to create a complete thermal and acoustic envelope. Understanding how the two components interact is important. OUTER ALUMINIUM 6063-T5 PA66 NYLON THERMAL BREAK INNER ALUMINIUM 6063-T5 5mm TEMPERED GLASS 20A / 27A Argon cavity 5mm TEMPERED GLASS INNER SASH OUTSIDE INSIDE Heat cool PA66 Nylon Break Tempered Glass Argon Cavity Aluminium 6063-T5 Cross-section of a thermal break frame with 5mm + 20A/27A + 5mm tempered IGU — the complete EZZO.SG system In EZZO.SG's standard specification, this means a 5mm tempered outer pane + 20 mm or 27 mm argon-filled cavity + 5mm tempered inner pane , seated within a thermally broken frame. The glass unit handles the centre-of-glass heat gain. The thermal break handles the edge-of-glass and frame heat gain. Together, they eliminate the primary pathways for unwanted heat transfer and create a genuinely insulating building envelope at the window. In a standard, non-thermally-broken aluminium system, you might invest in quality glass only to find that heat bypasses it via the frame. It is like insulating a wall but leaving the studs uninsulated — the thermal bridges dominate the overall performance. Performance Benefits in Singapore's Tropical Climate Singapore presents a specific set of conditions that thermal break frames are engineered to address. Unlike temperate climates where performance is measured against winter cold, Singapore's challenge is year-round heat, humidity, and intense solar radiation — often combined on the same facade simultaneously. The measurable performance gains of a properly specified thermal break system include: Reduced cooling load: By interrupting the frame-level thermal bridge, less heat enters the conditioned space. This directly reduces the tonnage of air-conditioning required to maintain a set temperature, with studies in tropical and subtropical climates typically showing 10–25% reductions in window-related heat gain when switching from non-broken to thermally broken frames with equivalent glass. Lower electricity bills: Singapore's residential electricity rates mean that sustained airc