{"id":18142,"date":"2026-05-01T13:33:44","date_gmt":"2026-05-01T08:03:44","guid":{"rendered":"https:\/\/aluminiummagazine.com\/mag\/?p=18142"},"modified":"2026-05-01T13:33:46","modified_gmt":"2026-05-01T08:03:46","slug":"why-aluminium-used-in-curtain-wall-systems","status":"publish","type":"post","link":"https:\/\/aluminiummagazine.com\/mag\/aluminium\/facade\/why-aluminium-used-in-curtain-wall-systems.html","title":{"rendered":"Why Aluminium Is Used in Curtain Wall Systems"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Walk through any major city and look up. The shimmering glass and metal envelopes of skyscrapers are almost always built around <strong>aluminium<\/strong>. It&#8217;s not a coincidence. Steel, wood, fiberglass, and even concrete have been tried, but aluminium has emerged as the global standard for curtain wall framing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Why? Because no other material delivers the perfect balance of <strong>strength, weight, corrosion resistance, formability, and cost<\/strong> \u2014 all at once.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This article breaks down the scientific and practical reasons why aluminium dominates curtain wall construction, from low-rise buildings to supertall towers.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Exceptional Strength-to-Weight Ratio<\/strong><\/h2>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-vs-steel-mullion-weight-comparison-1024x576.webp\" alt=\"Comparison graphic showing a lightweight aluminium mullion lifted by one worker versus a heavy steel mullion requiring two workers \u2014 equal strength but one-third the weight.\" class=\"wp-image-18144\" srcset=\"https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-vs-steel-mullion-weight-comparison-1024x576.webp 1024w, https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-vs-steel-mullion-weight-comparison-300x169.webp 300w, https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-vs-steel-mullion-weight-comparison-768x432.webp 768w, https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-vs-steel-mullion-weight-comparison.webp 1200w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>For the same structural performance, an aluminium mullion weighs about one-third of a steel equivalent \u2014 dramatically reducing handling, transport, and installation costs.<\/em><\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">Curtain walls are <strong>non-structural<\/strong> cladding \u2014 they only carry their own weight and wind loads, not floor or roof loads. But that self-weight still matters. A heavy facade requires massive anchors, stronger slab edges, and more crane capacity.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Aluminium has a density of approximately <strong>2.70 g\/cm\u00b3<\/strong> \u2014 about <strong>one-third that of steel<\/strong> (7.85 g\/cm\u00b3). Yet, with the right alloy and temper, its strength rivals mild steel.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th class=\"has-text-align-center\" data-align=\"center\">Material<\/th><th class=\"has-text-align-center\" data-align=\"center\">Density (g\/cm\u00b3)<\/th><th class=\"has-text-align-center\" data-align=\"center\">Yield Strength (MPa, typical)<\/th><th class=\"has-text-align-center\" data-align=\"center\">Strength-to-Weight Ratio<\/th><\/tr><\/thead><tbody><tr><td class=\"has-text-align-center\" data-align=\"center\">Aluminium 6063-T6<\/td><td class=\"has-text-align-center\" data-align=\"center\">2.70<\/td><td class=\"has-text-align-center\" data-align=\"center\">210<\/td><td class=\"has-text-align-center\" data-align=\"center\">78<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">Aluminium 6061-T6<\/td><td class=\"has-text-align-center\" data-align=\"center\">2.70<\/td><td class=\"has-text-align-center\" data-align=\"center\">275<\/td><td class=\"has-text-align-center\" data-align=\"center\">102<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">Mild Steel (A36)<\/td><td class=\"has-text-align-center\" data-align=\"center\">7.85<\/td><td class=\"has-text-align-center\" data-align=\"center\">250<\/td><td class=\"has-text-align-center\" data-align=\"center\">32<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\">Stainless Steel 304<\/td><td class=\"has-text-align-center\" data-align=\"center\">8.00<\/td><td class=\"has-text-align-center\" data-align=\"center\">215<\/td><td class=\"has-text-align-center\" data-align=\"center\">27<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Result:<\/strong> Aluminium offers <strong>2\u20133 times better strength-to-weight ratio<\/strong> than steel. This means thinner, lighter frames that are easier to handle, ship, and install \u2014 while still resisting high wind loads.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">For a detailed look at specific alloys used in curtain walls, check our guide on <strong><a href=\"https:\/\/aluminiummagazine.com\/mag\/aluminium\/aluminum-6063-alloy-aluminium-windows-doors-extrusion.html\">aluminium 6063 alloy for windows, doors, and extrusion<\/a><\/strong>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Natural Corrosion Resistance<\/strong> (No Rust)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Steel rusts. Wood rots. Aluminium? It <strong>passivates<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When exposed to oxygen, aluminium instantly forms a thin, transparent, and <strong>self-healing<\/strong> oxide layer (Al\u2082O\u2083). This layer is only 2\u20133 nanometers thick but is incredibly stable and adheres tightly to the metal. If scratched, the oxide reforms within milliseconds.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">This is why aluminium curtain walls last <strong>50+ years<\/strong> without structural degradation \u2014 even in coastal salt spray or industrial pollution.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Enhanced Protection Options<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">For aggressive environments, architects specify:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Anodizing<\/strong> \u2013 Electrochemically thickens the natural oxide layer. Offers 25+ years of maintenance-free life. Colors range from clear to bronze to black.<\/li>\n\n\n\n<li><strong>Powder Coating<\/strong> \u2013 Adds a durable, colored polymer layer (usually 60\u201380 microns). Excellent UV resistance and design flexibility.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Learn the difference between these two finishes in our article: <strong><a href=\"https:\/\/aluminiummagazine.com\/mag\/magazine\/powder-coating-vs-anodizing.html\">powder coating vs anodizing<\/a><\/strong>.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Infinite Extrudability \u2013 Complex Shapes Made Easy<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Curtain walls are not simple rectangles. They require:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Pressure-equalized drainage cavities<\/strong> (internal gutters)<\/li>\n\n\n\n<li><strong>Gasket retention grooves<\/strong><\/li>\n\n\n\n<li><strong>Thermal break slots<\/strong> (for inserting polyamide strips)<\/li>\n\n\n\n<li><strong>Interlocking male-female connectors<\/strong> (for unitized systems)<\/li>\n\n\n\n<li><strong>Weep hole channels<\/strong> (pre-formed, not drilled)<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Aluminium is <strong>extruded<\/strong> by forcing a heated billet through a steel die. This process can create virtually any cross-section with <strong>tolerances as tight as \u00b10.1 mm<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">No other curtain wall material \u2014 steel, fiberglass, or uPVC \u2014 offers such design freedom at a reasonable cost. Complex multi-cavity profiles are produced in a single pass, reducing fabrication and assembly time.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">For more on extrusion technology, read our overview of the <strong><a href=\"https:\/\/aluminiummagazine.com\/mag\/aluminium\/aluminium-extrusion.html\">aluminium extrusion process<\/a><\/strong>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Thermal Break Compatibility<\/strong><\/h2>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-thermal-break-mullion-cutaway-1024x576.webp\" alt=\"Cutaway drawing of an aluminium curtain wall mullion with a polyamide thermal break strip separating warm interior from cold exterior to prevent heat loss.\" class=\"wp-image-18145\" srcset=\"https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-thermal-break-mullion-cutaway-1024x576.webp 1024w, https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-thermal-break-mullion-cutaway-300x169.webp 300w, https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-thermal-break-mullion-cutaway-768x432.webp 768w, https:\/\/aluminiummagazine.com\/mag\/wp-content\/uploads\/2026\/05\/aluminium-thermal-break-mullion-cutaway.webp 1200w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>A polyamide strip inserted between interior and exterior aluminium sections dramatically reduces thermal conductivity, making aluminium curtain walls energy-efficient even in cold climates.<\/em><\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">Raw aluminium conducts heat efficiently (approx. <strong>205 W\/m\u00b7K<\/strong>). In cold climates, this can cause <strong>thermal bridging<\/strong> \u2014 heat escaping through the frame, leading to condensation and energy loss.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The solution? <strong>Thermal break technology<\/strong>.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">A thermal break curtain wall uses a low-conductivity material (typically <strong>polyamide 6.6 or polyurethane foam<\/strong>) inserted between the interior and exterior aluminium sections. This reduces frame U-values from ~5.7 W\/m\u00b2\u00b7K (non-thermal) to as low as <strong>1.4 W\/m\u00b2\u00b7K<\/strong> or better.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Aluminium&#8217;s machinability allows precise crimping or pouring of thermal break strips directly into the extrusion profile. This is far more reliable than attempting thermal breaks with steel or uPVC.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">To understand how thermal breaks work in fenestration, explore our guide: <strong><a href=\"https:\/\/aluminiummagazine.com\/mag\/efficiency\/what-are-thermal-break-aluminium-windows.html\">what are thermal break aluminium windows?<\/a><\/strong>.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Dimensional Stability &amp; Low Maintenance<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Unlike wood, aluminium does not swell, warp, crack, or rot. Unlike some plastics, it does not creep under sustained load or become brittle from UV exposure.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Coefficient of thermal expansion:<\/strong> 23.1 \u00d7 10\u207b\u2076 \/\u00b0C (similar to glass and concrete, reducing differential movement stress).<\/li>\n\n\n\n<li><strong>Modulus of elasticity:<\/strong> 69 GPa (stiff enough to limit deflection to L\/175 or better).<\/li>\n\n\n\n<li><strong>Maintenance:<\/strong> Occasional washing is all that&#8217;s needed. No painting, sealing, or rust removal.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">This stability means curtain wall gaskets and seals last longer because the frame doesn&#8217;t deform unpredictably.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Compatibility with Glass &amp; Other Infills<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Curtain walls are glass-dominant. Aluminium and glass are <strong>thermally and mechanically compatible<\/strong>:<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Similar thermal expansion rates reduce seal shear stress.<\/li>\n\n\n\n<li>Aluminium&#8217;s stiffness provides uniform support to glass edges, preventing stress fractures.<\/li>\n\n\n\n<li>Anodized or powder-coated aluminium offers neutral color matching to glass tones (clear, bronze, gray, black).<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Additionally, aluminium frames can accommodate <strong>spandrel panels<\/strong>, <strong>metal infills<\/strong>, or <strong>ventilation louvers<\/strong> within the same system \u2014 a flexibility not possible with glass-only systems.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For the best glass pairings with aluminium, read our article: <strong><a href=\"https:\/\/aluminiummagazine.com\/mag\/glass\/best-aluminum-window-glass-hot-climates-energy-efficient.html\">best aluminium window glass for hot climates<\/a><\/strong>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Recyclability &amp; Sustainability<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Sustainability is no longer optional \u2014 it&#8217;s a requirement for LEED, BREEAM, and other green building certifications.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Aluminium is <strong>infinitely recyclable<\/strong> without loss of properties. Recycling uses only <strong>5% of the energy<\/strong> required to produce primary aluminium. Today, many curtain wall systems use profiles containing <strong>70\u201380% post-consumer recycled content<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Stick and unitized systems can be fully disassembled at end-of-life. The frames are melted down and reborn as new extrusions. No other curtain wall material closes the loop so cleanly.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For more on aluminium&#8217;s environmental advantages, see our article: <strong><a href=\"https:\/\/aluminiummagazine.com\/mag\/aluminium\/packaging\/why-aluminium-reigns-supreme-in-packaging.html\">why aluminium reigns supreme in packaging<\/a><\/strong> \u2014 the same recycling logic applies to building envelopes.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Cost-Effectiveness Over Lifecycle<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Initial material cost: Aluminium is more expensive than uPVC or basic steel. But total <strong>lifecycle cost<\/strong> is far lower:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Cost Factor<\/th><th>Aluminium<\/th><th>uPVC<\/th><th>Steel<\/th><th>Wood<\/th><\/tr><\/thead><tbody><tr><td><strong>Initial material<\/strong><\/td><td>Medium<\/td><td>Low<\/td><td>Low-Medium<\/td><td>Medium-High<\/td><\/tr><tr><td><strong>Fabrication<\/strong><\/td><td>Low (extrude once)<\/td><td>Medium<\/td><td>High (welding)<\/td><td>High (joinery)<\/td><\/tr><tr><td><strong>Installation<\/strong><\/td><td>Low (lightweight)<\/td><td>Low<\/td><td>High (heavy)<\/td><td>Medium<\/td><\/tr><tr><td><strong>Maintenance (50 years)<\/strong><\/td><td>Very Low<\/td><td>Medium (re-sealing, fading)<\/td><td>High (rust, painting)<\/td><td>High (painting, sealing)<\/td><\/tr><tr><td><strong>Replacement value<\/strong><\/td><td>High (recyclable)<\/td><td>Low (landfill)<\/td><td>Medium<\/td><td>Low-Medium<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Verdict:<\/strong> Aluminium offers the lowest <strong>lifecycle cost<\/strong> for buildings over 20 years \u2014 and most curtain walls last 50+ years.<\/p>\n<\/blockquote>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Common Aluminium Alloys for Curtain Walls<\/strong><\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th class=\"has-text-align-center\" data-align=\"center\">Alloy<\/th><th class=\"has-text-align-center\" data-align=\"center\">Temper<\/th><th class=\"has-text-align-center\" data-align=\"center\">Yield Strength (MPa)<\/th><th>Primary Use<\/th><\/tr><\/thead><tbody><tr><td class=\"has-text-align-center\" data-align=\"center\"><strong>6063<\/strong><\/td><td class=\"has-text-align-center\" data-align=\"center\">T5 \/ T6<\/td><td class=\"has-text-align-center\" data-align=\"center\">145\u2013210<\/td><td>Standard extrusions, windows, doors, stick curtain walls<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\"><strong>6061<\/strong><\/td><td class=\"has-text-align-center\" data-align=\"center\">T6<\/td><td class=\"has-text-align-center\" data-align=\"center\">275<\/td><td>High-strength mullions, unitized anchors, heavy-load areas<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\"><strong>6005<\/strong><\/td><td class=\"has-text-align-center\" data-align=\"center\">T5<\/td><td class=\"has-text-align-center\" data-align=\"center\">215<\/td><td>Thicker extrusions for high wind zones<\/td><\/tr><tr><td class=\"has-text-align-center\" data-align=\"center\"><strong>6082<\/strong><\/td><td class=\"has-text-align-center\" data-align=\"center\">T6<\/td><td class=\"has-text-align-center\" data-align=\"center\">260<\/td><td>Marine and industrial facades (higher corrosion resistance)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">For a complete list of alloy properties, browse our <strong><a href=\"https:\/\/aluminiummagazine.com\/mag\/aluminium\/series\/aluminum-1000.html\">aluminium alloys series guide<\/a><\/strong>.<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>A Note on Limitations<\/strong> (<em>And How Engineers Overcome Them<\/em>)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Aluminium is not perfect. Two key limitations exist \u2014 and both have proven solutions:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Limitation<\/th><th>Solution<\/th><\/tr><\/thead><tbody><tr><td><strong>High thermal conductivity<\/strong> (energy loss)<\/td><td>Add polyamide thermal breaks \u2014 reduces heat transfer by up to 80%<\/td><\/tr><tr><td><strong>Lower strength than steel<\/strong><\/td><td>Use deeper mullions (150\u2013200 mm) or switch to 6061-T6 \/ 6082-T6 alloys<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">These solutions are mature, proven, and widely available from every major curtain wall manufacturer.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div style=\"height:75px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Final Verdict: <em>Why Aluminium Wins<\/em><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Other materials have niche applications:<\/p><div class=\"pai-ad\" style=\"min-height:250px;visibility:hidden;\"><span style=\"display: block; text-align: center; font-size: 10px; margin: 0 0 10px 0; color: #999999;\">Ads<\/span>\r\n<!-- Display-300x250-1 -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:inline-block;width:300px;height:250px\"\r\n     data-ad-client=\"ca-pub-3838168351244230\"\r\n     data-ad-slot=\"9933646018\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><\/div>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Steel<\/strong> is still used for mega-spans or bomb-blast resistance.<\/li>\n\n\n\n<li><strong>uPVC<\/strong> is common in residential windows but lacks strength for high-rise curtain walls.<\/li>\n\n\n\n<li><strong>Wood<\/strong> is beautiful but requires constant maintenance and has limited span capacity.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">But for the vast majority of commercial curtain walls \u2014 from 5-story offices to 100-story skyscrapers \u2014 <strong>aluminium is the undisputed champion<\/strong> because it uniquely offers:<\/p><script>document.addEventListener(\"DOMContentLoaded\",function(){\n        if(window.innerWidth <= 768){\n            if (\"immediate\" === \"delay\") {\n                setTimeout(function(){document.querySelectorAll(\".pai-ad\").forEach(el=>el.style.visibility=\"visible\")},0);\n            } else if (\"immediate\" === \"scroll\") {\n                window.addEventListener(\"scroll\",function(){\n                    let s=window.scrollY\/(document.body.scrollHeight-window.innerHeight);\n                    if(s>0.1){\n                        document.querySelectorAll(\".pai-ad\").forEach(el=>el.style.visibility=\"visible\");\n                    }\n                });\n            } else {\n                document.querySelectorAll(\".pai-ad\").forEach(el=>el.style.visibility=\"visible\");\n            }\n        } else {\n            document.querySelectorAll(\".pai-ad\").forEach(el=>el.remove());\n        }\n    });<\/script>","protected":false},"excerpt":{"rendered":"<p>Walk through any major city and look up. The shimmering glass and metal envelopes of skyscrapers are almost always built around aluminium. It&#8217;s not a coincidence. Steel, wood, fiberglass, and even concrete have been tried, but aluminium has emerged as the global standard for curtain wall framing. Why? Because no other material delivers the perfect &#8230; <a title=\"Why Aluminium Is Used in Curtain Wall Systems\" class=\"read-more\" href=\"https:\/\/aluminiummagazine.com\/mag\/aluminium\/facade\/why-aluminium-used-in-curtain-wall-systems.html\" aria-label=\"Read more about Why Aluminium Is Used in Curtain Wall Systems\">Read more<\/a><\/p>\n","protected":false},"author":12,"featured_media":18143,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4156],"tags":[4157,4158],"class_list":["post-18142","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-facade","tag-curtain-wall","tag-facade"],"_links":{"self":[{"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/posts\/18142","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/comments?post=18142"}],"version-history":[{"count":1,"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/posts\/18142\/revisions"}],"predecessor-version":[{"id":18146,"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/posts\/18142\/revisions\/18146"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/media\/18143"}],"wp:attachment":[{"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/media?parent=18142"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/categories?post=18142"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/aluminiummagazine.com\/mag\/wp-json\/wp\/v2\/tags?post=18142"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}