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Perforation preferences: A blank canvas for the creation of perforated elements

Perforators can help contractors and builders by opening the door to both new and established ways of obtaining optimal solutions for their project needs. Perforators can produce a wide range of perforation patterns, sizes and shapes in a host of various materials. These capabilities provide a broad, blank canvas for the creation of new functional and aesthetic elements that add to a building's appeal. A seasoned perforator will also provide solutions and ideas that could lead to designs that you might not have thought possible. This collaborative relationship will allow you to leverage off the perforator's experience and knowledge for improved aesthetics, increased functionality and greater cost efficiencies.

The Checklist

On the occasion that the architectural prints are unspecified for the job, it is important to consider the following before ordering perforated metal. The following is an abbreviated checklist for any contractor inquiring about the perforated metal required for the job.

  • Quantity-State the number of perforated pieces or square footage of coverage required.
  • Thickness-Specify in gauge numbers or in decimal inches, such as 1/4-inch (6-mm) thick, 16 gauge, 0.040 inch (1 mm), etc.
  • Metal-State type of metal required: aluminum, stainless steel, copper, galvanized, etc.
  • Perforation Size-Specify the size of perforated hole in inches, such as 0.125 inch (3 mm), 0.375 inch (9.5 mm), etc.
  • Arrangement of Perforations-Specify "staggered," "straight line" or other patterns.
  • Finish-Specify powder coating, anodizing, Kynar, plating or degreasing.

Thickness of the Material

Thin material would be appropriate for nonstructural applications or strictly for a decorative element where deflection is not going to be a problem. Thin material can also be used if the contractor needs to form in the field (following the curvature of the building). Material thickness is ultimately the responsibility of an architect or a structural engineer in factoring things such as wind load, material span and attachment methods, to name a few.

Metal Options

Accurate Perforating Inc., Chicago, can perforate anything from stainless steel to copper to brass and bronze. There is no limit to the type of metal. Often times, architects want to look mainly at copper or brass for purely aesthetic purposes. But the raw material cost is so much more expensive using material like copper or brass. A similar look can be achieved with powder coating, anodizing, etc.

Another issue with material type is corrosion resistance. There are several options to minimize corrosion, beginning with the material type (stainless steel, aluminum or galvanized) and again by using powder coating, anodizing or other secondary finishes.

Interior Applications

For an interior application, regular ferrous can still be appropriate if the material needs to be protected. Galvanized and electro-galvanized offer superior corrosion resistance for carbon steel. However, when you perforate the metal, you are exposing an edge of the ferrous material and creating a potential for rust. Therefore, a second finish of paint or powder coat is still necessary.

The Illinois State Emergency Operations Center, Springfield

In March 2004, the state of Illinois announced that the new State Emergency Operations Center would open in Springfield and would house the State Terrorism Intelligence Center, the Illinois Terrorism Task Force and other emergency personnel. A local design firm specified the use of 18,000 square feet (1,672 m2) of perforated copper panels as exterior classing to the SEOC. A local subcontractor was in charge of the installation of the panels. Thanks to a progressive pricing structure and attentive, detailed service during the proposal process, Accurate Perforating was assigned the project and given the specifications.

The paneling was formed using a special 6-inch- (152-mm-) deep sheet made from 32-ounce copper, double the typical 16-ounce weight. The screen was perforated with 1/2-inch (13-mm) round holes on 3.4-inch (86-mm) staggered centers. The screen's overlapping panels were bolted to a tubular frame affixed to the building's exterior. The panels were attached to the frame in overlapping sections. However, the design had to be customized to ensure that when the panels were installed, the holes would line up where the panels overlapped.

Accurate Perforating's attention to details and advanced CAD capabilities identified the fit of each panel against each other and to its respective place on the frame. The preproduction design was authorized and the production run began. The fabricated parts were shipped to Springfield and attached to the structure-they fit perfectly.

Balcony-21 Kristin Drive, Schaumburg, Ill.

Decades before, the balconies of this brick apartment building were created with painted plywood panels attached to aluminum railings for safety. This combination produced a dated outer shell and a barrier that obscured sunlight from the apartment interiors.

Understanding the building owner's need to creatively update the balconies with minimal disruption and within budget, Accurate Perforating knew the importance of merging function, aesthetics and cost efficiencies. The goal was an open look that meets code and is just as appealing from the outside in as from the inside out. Accurate Perforating, with the help of a local partner, created custom panels of perforated metal with 3/16-inch (5-mm)round holes on a 1/2-inch staggered pattern with large solid borders. They combined this with a thinner, 0.125-inch-thick 5005 aluminum to meet the project budget without sacrificing safety or beauty.

A clear anodized finish was recommended for the balcony to retard the rust, peeling or fading that can occur with exterior metal product applications. Durability of the panels was also a key element, as residents use the balconies as an extension of daily living. Clear anodizing was an inexpensive solution in line with aesthetic preferences in the architectural community. Installation was made easy with screws and pop rivets. Because the existing railings were aluminum, no bushings were needed to prevent galvanic reaction.

Accurate Perforating played a significant role in making a large property exceedingly marketable. The large-scale design and implementation solution met all structural requirements of the project while providing an aesthetically pleasing look that was the right fit for the building and the budget.

Daniel Cohen is the special projects manager at Accurate Perforating Co., Chicago. For more information, visit