Aluminum (Construction)
A lightweight, corrosion-resistant metal for framing, glazing systems, and trim.
Quick Answer
Aluminum in construction is a lightweight, corrosion-resistant metal, usually extruded into framing for curtain walls, storefronts, and windows or formed into trim, panels, and sunshades. It is anodized or coated for durability, and because it conducts heat readily, exterior frames typically include thermal breaks to meet energy requirements.
The Full Picture
Aluminum is valued in buildings for its low weight, workability, and natural resistance to corrosion. Pure aluminum is soft, so building products use alloys, and architectural extrusions commonly use alloys of the 6000 series such as 6063. Extrusion allows complex profiles with integrated glazing pockets, drainage paths, and screw channels, which is why aluminum dominates storefront, curtain wall, and window frames.
Aluminum glazing systems differ in how they are built. Storefront is generally a lower-height, site-glazed system for ground-floor entrances and retail. Curtain wall is a non-structural exterior wall system hung from the building structure, often factory-assembled into units for taller buildings. Both rely on gaskets, sealants, and drainage to manage water, and they need coordination with the structure for movement and anchorage.
Finish and thermal performance are major specification topics. Common finishes are anodizing and high-performance painted coatings, with industry specifications from the fenestration industry setting performance expectations for color retention and durability. Aluminum conducts heat easily, so exterior frames use thermal breaks, an insulating polymer separating inside and outside metal, to reduce heat loss and condensation risk, and glass selection works together with the frame to meet the energy code.
Aluminum is also used for composite and solid panels, louvers, sunshades, railings, and trim. For preconstruction teams, aluminum glazing is usually a specialty subcontract with shop drawings, mockups, and long lead times, so early procurement and coordination with the structure, glass, and air and water barriers are key. Aluminum is highly recyclable, which affects embodied carbon discussions.
Real Examples
Common Misconceptions
People assume: Aluminum frames are good insulators because they are lightweight.
Actually: Aluminum conducts heat very well. Energy-efficient frames use thermal breaks and carefully selected glass to control heat flow.
People assume: Storefront and curtain wall are the same system.
Actually: They are different systems. Storefront is typically lower-height and glazed in place, while curtain wall is designed for greater heights, building movement, and often factory-assembled units.
Frequently Asked Questions
What is a thermal break in aluminum framing?
A strip of low-conductivity material, usually a polymer, that separates the interior and exterior aluminum so heat does not flow straight through the frame.
What finishes are used on architectural aluminum?
Common finishes are anodizing and high-performance painted coatings such as fluoropolymer systems, selected for appearance and durability per the specification.
What is the difference between storefront and curtain wall?
Storefront is generally a lower-rise, site-glazed system at ground level. Curtain wall is a non-structural exterior wall system for taller buildings, often built from factory-assembled units.
Is aluminum recyclable?
Yes. Aluminum can be recycled repeatedly with much less energy than primary production, though embodied carbon depends on the source and the project's accounting method.