Architecturally Exposed Structural Steel (AESS)

Architecturally exposed structural steel frame supporting a canopy

Architecturally exposed structural steel (AESS) is a meticulously fabricated and finished form of steel that creates new design possibilities.

Unlike regular structural steel, AESS is crafted to achieve both a structural purpose and an aesthetic one. To achieve a look that will last for generations, all debris, oil, and grease must be removed and all welds must be ground smooth. The result is a striking, very low-maintenance building feature that will withstand use and climate.

Shawnee Steel & Welding offers architecturally exposed structural steel in four categories, all hand-finished. Pieces that are more visible or that will be touched may require a higher AESS grade.

Types of AESS Solutions We Offer


Basic Elements

AESS 1 is the default specification for structural steel that will be visible. Steel is commercially blast clean and sharp edges are ground smooth.


Feature Elements Not in Close View

AESS 2 is appropriate for elements that will be viewed from more than 20 feet away, when finishing details are not as visible by the human eye. Fabrication marks are not visible; welds are uniform and smooth but may be visible.


Feature Elements in Close View

AESS 3 is ideal for elements that can be viewed closely within 20 feet away or that are within a person’s reach. Mill marks are removed, hollow structural section weld seams are oriented to have reduced visibility, cross-sectional abutting surfaces are aligned, and joint gap tolerances are minimized.


Showcase Elements

“Showcase” AESS is the highest grade of architecturally exposed structural steel. AESS 4 adds even more finishing to ensure a flawless surface. Welds are blended or contoured and weld show-through is minimized. Surfaces are filled and sanded and hollow structural sections are not visible. AESS 4 is most often used when the form is intended to be the primary design focus.

AESS Custom:

Custom AESS Solution

We help architects determine the right grade of AESS for their projects by evaluating a number of factors:

Architecturally Exposed Structural Steel (AESS): An Architect's Guide

Complete the form below to download our free guide to AESS.

Download AESS Brochure

AESS Projects