Architectural Record BE - Building Enclosure

High-Performance Facade Solutions

First impressions are important, but it’s what’s on the inside that counts.
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Sponsored by Construction Specialties, EXTECH/Exterior Technologies, Inc., New Millennium Building Systems, and SAFTI FIRST Fire-Rated Glazing Solutions
By Peter J. Arsenault, FAIA, NCARB, LEED AP

Facade Specialty Details

When it comes to facade design, the one thing that is certain is that there will be design and construction details to address. Those details can include connections, attachments, joints, or other conditions. Two things in particular deserve some attention here which are very common elements of many commercial building designs—expansion joints and architectural louvers in openings. Both of these elements can have a significant impact on the successful functioning of a facade in terms of the purpose they are intended to serve plus their integration with the surrounding facade materials. Additionally, they can have either a positive, negative, or neutral impact on the overall building design scheme depending on how they are handled. With the above in mind, let’s take a closer look at each of these specialty conditions.

Facade Expansion Joint Covers

Most commercial buildings of any size require expansion joints between sections of the structure to allow a building to expand, contract, or shift laterally due to imposed forces. Those movements can come from temperature changes causing materials to expand or contract, winds that move or sway the building, settlement over time, or seismic events. A well-designed series of expansion joints will allow sections of the building to move independently of each other without damaging either the structure or the finish materials.

Of course, leaving an expansion joint open to the elements on a facade is not a realistic solution. Hence, those joints need to be covered in a manner that maintains the integrity of the joint and the facade, both for appearance as well as performance, while still allowing for independent building movement on either side of the joints. Metal expansion joint covers are typically manufactured to allow for the anticipated building movement by using components that are designed to slide or otherwise pass by each other or adjacent building portions. The means to do that will vary by manufacturer and by type of expansion joint cover, and manufacturers typically provide a range of product offerings to suit different conditions. Selecting the proper one will help assure that the building and the facade are protected from damage when, or if, building movement occurs.

In addition to allowing for movement, these expansion joint covers also need to be able to insulate and protect the joint opening from outside elements. If water or moisture make their way into the joint opening, then the building could be susceptible to leaking, moisture damage, mold, or other deterioration which could cause failure. Therefore, metal covers with a water and vapor barrier installed behind the cover are common, as are fully watertight solutions that fit into a joint opening. Similarly, if airborne dust, dirt, or other objects get in behind the expansion joint cover, then it may not function properly since the anticipated movement or sliding of components could be impaired. Hence the expansion joint cover needs to seal against such penetration of foreign matter as well.

While the need for expansion joints and covers is clear, there is a design aspect that needs to be addressed. Often, the architect’s main design concern is focused on concealing expansion joint covers so as not to have a significant impact on the overall building facade design. Manufacturers have responded with multiple options for covers that can be infilled with whatever facade materials are specified for the rest of the building, thus creating a rather continuous appearance. The metal of the expansion joint cover itself can also be custom colored to match a building’s facade and become virtually undetectable.

When an expansion joint cover type is identified that meets the aesthetic criteria for a project, architects can then work with manufacturers to verify that the performance criteria is met. Some provide considerable technical assistance and, when applicable, they can conduct cycle testing on a joint cover to verify their performance. From that standpoint, architects should have confidence that the solution they specify will both perform well and blend into the overall facade design in a minimally invasive way.

Kevin Smith, PE, is the engineering manager at Construction Specialties and provides technical assistance to architects on a regular basis regarding expansion joint covers. He points out that “Many of our expansion joint covers have been reimagined over the years to accommodate architects’ demand for better integration with their designs. Each project that we work on is an opportunity for us to evaluate how to refine our solutions for better performance, resiliency, and concealment.” Clearly, then, there is an ongoing interest within the industry to accommodate project specific requirements that address all aspects of incorporating expansion joints successfully into a building facade.

Photo of a building facade joint cover

Images courtesy of Construction Specialties

Expansion joints in a building facade are often necessary but need to be protected with an expansion joint cover. Selecting the best product involves meeting the performance needs of a project but can also involve selecting one that allows matching facade material to be inserted in the face of cover to blend with the overall design.

 

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Originally published in Architectural Record

Notice

Academies
High-Performance Facade Solutions
Buyer's Guide
XLS Seismic Exterior Wall Cover
Construction Specialties’ XLS covers are designed for applications where concealment is desired and where seismic activity is expected. The system has a structural ladder-frame assembly and can accept materials to match the facade. Each unit has two heavy-duty magnetic closures and a pulley system to ensure the system remains closed.
Construction Specialties
http://www.c-sgroup.com/ejc
RSH-5700 Storm-Resistant Louver
Construction Specialties’ Storm-Resistant Louvers provide the highest level of water protection while also allowing for excellent airflow. In addition to exceptional AMCA-certified air and water performance, model RSH-5700 has the ability to integrate into metal panel and unitized curtain-wall systems unilizing project-specific custom extrusions.
Construction Specialties
www.c-sgroup.com/louvers
LIGHTWALL 3440® Interlocking Wall System
This translucent wall system offers beauty and durability with vertical panels that can extend up to 54 feet. Its tongue-and-groove joinery provides an unbroken appearance, and it delivers an insulation value of up to R-5 for 50-millimeter-thick panels. The LIGHTWALL 3440 is highly impact resistant and has undergone a host of ASTM air, water, structural, and flammability testing.
EXTECH/Exterior Technologies, Inc.
extechinc.com/lightwall
Transform Construction with Innovative Facades
Architectural deck provides aesthetic appeal for exposed metal deck systems placed in roof-ceiling and cladding assemblies. With New Millennium Building Systems as your early-stage collaborative resource, architects and owners can specify architectural deck with confidence. Download our Architectural Deck Ceiling & Cladding Systems Design Guide at www.newmill.com/arch.
New Millennium Building Systems
www.newmill.com
GPX FireFloor
This is a 1- and 2-hour fire-resistive glass floor system with the largest tested and listed individual glass panel sizes in butt-glazed and fully supported assemblies. Both the fire-resistive glass and structural steel framing grid are USA made by SAFTI FIRST for a complete turn key solution.
SAFTI FIRST Fire-Rated Glazing Solutions
safti.com/gpx-fire-floor/