BENEFITS OF EXTRUDED ALUMINUM

The most abundant mineral in the earth’s crust, aluminum is derived from bauxite, which is mined from the earth. After processing, the resultant alumina undergoes a smelting and alloying process that produces solid logs of cast metal from which extruded aluminum shapes or profiles are made. Most extruded shapes for architectural use are fabricated from AA 6063, an aluminum alloy, with magnesium and silicon as the alloying elements. Type 6063-T5 aluminum, commonly referred to as the architectural alloy, has a very smooth surface and is the best alloy suited for anodizing applications. The T5 designation indicates it has been artificially aged and moderately heat treated. Aluminum extrusion is a highly versatile metal-forming process that has a wide array of physical characteristics, including:

• It can be recycled and retains a high scrap value. It can be recycled indefinitely without losing any of its superior characteristics, making it especially appealing according to both environmental and economic criteria.
• It’s lightweight. It weighs about one-third of most other metals, which makes it easier to handle and less expensive to ship.
• It’s strong. Profiles can be made as strong as needed for most applications. Having the strength of a rigid metal prevents swelling and buckling.
• It’s weather resistant. Cold-weather applications are particularly well served by aluminum because, as temperatures fall, aluminum actually becomes stronger.
• It’s fire resistant.
• It does not rust because aluminum is protected by its own naturally occurring oxide film.
• It’s resilient and can spring back from the shock of impact.
• It’s not combustible. Even at extremely high temperatures, it does not produce toxic fumes.
• Different finishes are available. It can be finished with liquid paint (including acrylics, alkyds, polyesters, and others), powder coatings, and anodizing.
• It offers seamless profiles. Complex shapes can be realized in one-piece extruded aluminum sections without having to employ mechanical joining methods. The resultant profile typically is stronger than a comparable assemblage and less likely to leak or loosen over time.
• It can be joined in many ways. Extruded aluminum sections can be joined by all major methods in use today.
• It’s economical because it’s relatively inexpensive and may not require long lead times. Even short-run prototypes often can be produced at moderate cost.
• It can be easily manufactured to accepted standard dimensional tolerances.

CASE STUDY: ALUMINUM TRIM FOR PREPARATORY SCHOOL

Photo courtesy of TAMLYN

Extruded aluminum trim painted black accents the reveals in the facade to bring variation to the fiber cement panel.

Photo courtesy of TAMLYN

At the corner, a reveal corner (see below) was used to accent and give depth.

Peak Preparatory School in Dallas, developed for Uplift Education and designed by HKS Inc., is a steel frame construction with a combination of brick and fiber cement panel and lap sidings. Premanufactured extruded aluminum trim in multiple finishes was used to accent corners in the lap siding and to create a varied and interesting facade with the fiber cement panel.

CASE STUDY: MANY USES OF ALUMINUM TRIM FOR NEW HOPE HOUSING INC.

Photo by Hiebert Photography, Houston

New Hope Housing used extruded aluminum trim for window and door headers; to terminate between fiber cement and brick or stucco; to accent the fiber cement; and on corner conditions.

Photo by Hiebert Photography, Houston

Extruded aluminum trims were used for horizontal, vertical, and corner conditions for fiber cement panels and for the corner and transitions in the fiber cement lap siding.

The new 4114 Perry affordable housing facility in Houston, developed by New Hope Housing Inc. and designed by Val Glitsch, FAIA, LEED AP, Houston, is a three-story wood construction on a concrete foundation. The exterior is a mix of brick, stucco, fiber cement panels, and lap siding. Premanufactured aluminum trim was placed above, below, and between the different types of fiber cement siding, above windows and doors, and below the siding over brick. It also was used for both inside and outside corners and where panels meet the lap siding boards. “The alternative to premanufactured trim? Wood trim gives a very different aesthetic. It is bulkier and, for water infiltration concerns, can only be used for vertical joints,” Glitsch says. “We could have had a metal shop make up the trim pieces, but that’s not always a good way to get a quality, consistent, cost-effective product. And the heavier-weight ‘extreme trim’ we used makes it easier to install the product properly.”