Manufactured Stone Veneer Systems

The architectural landscape of the Southeastern United States boasts a diverse range of styles, from the historic colonial plantations to modern urban developments. A material that has found a strong foothold in both traditional and contemporary designs within this region is Manufactured Stone Veneer (MSV). This architectural material not only offers a sense of aesthetic versatility but also presents architects and contractors with a unique set of considerations when it comes to building code requirements and ASTM standards.

By mastering MSV detailing and installation practices for optimal performance and durability, and by staying informed on code requirements and ASTM standards, professionals can enhance their expertise and consistently meet — and exceed — regional expectations.

MSV offers a wide range of styles and colors, making it versatile for any project. From rustic, natural stone textures to sleek, modern profiles, it complements all architectural designs. With color options from earth tones to vibrant hues, MSV allows builders and designers to achieve any desired aesthetic, from classic to contemporary.

Key Components of MSV Systems

MSV is a non-load bearing exterior or interior wall covering that mimics natural stone. The key components of complete MSV systems typically include:

• Lath or Wire Mesh: A galvanized metal mesh used to create a surface for the mortar to adhere to. It’s fastened to the structure and serves as the base for the MSV.

• Mortar: A cement-based adhesive that binds the MSV units to the substrate or lath. Mortar is also used to fill gaps between units (grout).

• Water-Resistive Barrier (WRB): A crucial component to prevent water infiltration, installed behind the lath to protect the structure from moisture damage.

• Weep Screed or Flashing: Installed at the base of the system to allow moisture to escape and ensure proper drainage, preventing water buildup behind the veneer.

• Control Joints and Expansion Joints: Integrated into the system to accommodate movement, prevent cracking, and enhance the system’s durability over time.

These components work together to ensure a durable, weather-resistant, and aesthetically appealing installation.

Building Code Requirements

In the Southeast, building codes are typically adapted from the International Building Code (IBC) and International Residential Code (IRC), which are integrated into local regulations with specific amendments. These codes delineate the minimum requirements to safeguard public health, safety, and general welfare.

MSV systems are scrutinized under the building code requirements for exterior wall finishes. Architects and contractors must ensure that their MSV installations comply with the local amendments to the IBC/IRC and any additional provisions set forth by local jurisdictions, which often require additional wind load and moisture management strategies due to the region’s susceptibility to hurricanes and high humidity levels.

ASTM Standards Governing MSV

ASTM International sets technical standards for materials, including MSV. Noteworthy standards include ASTM C1670/C1670M for the stone veneer units themselves and ASTM C1714/C1714M for the mortar used in the setting bed. These standards outline the material properties required for manufactured stone, ensuring the quality and durability of the MSV units and the mortar that secures them in place.

Industry Recommendations

Gaps that are not covered by existing building code requirements are addressed through industry recommendations, such as those from the Concrete Masonry & Hardscapes Association (CMHA). These recommendations provide guidance on best practices for installation beyond what is codified, ensuring that MSV systems not only meet but exceed the minimum safety and performance standards.

Applications

In the Southeast region, the application of MSV must consider the climatic conditions, which can include extreme weather events. For example, in coastal areas prone to hurricanes, MSV systems must withstand high-velocity wind and driven rain. This has led to the development of more robust water-resistive barriers and anchoring systems that provide enhanced resistance to wind uplift and moisture intrusion. A notable project showcasing this approach is the Savannah Waterfront Marriott in Georgia, where MSV was successfully applied to withstand the coastal city’s challenging weather conditions while maintaining the historical aesthetic the area is known for.

Another example is a residential development in Charleston, South Carolina, where MSV was utilized to replicate the city’s famed cobblestone look. Here, MSV had to adhere to strict historical district guidelines, which dictated not only the appearance but also the resilience of the materials used. The application in this case not only conformed to the local building codes and ASTM standards but also respected the cultural heritage of the environment.

Detailing and Installation Practices

Detailing and installation are as critical to the success of an MSV system as the material itself. In the Southeast, professionals must account for thermal movement, moisture management, and other climate-specific concerns. Installation begins with a properly installed water-resistive barrier, which in the Southeast must be particularly robust. The metal lath and scratch coat follow, which should be corrosion-resistant to combat the humid environment.

Correct detailing around openings, flashings, weep screeds, and at the foundation are essential to prevent water ingress and to manage any water that does penetrate the veneer. Installation practices must also account for proper joint spacing and the use of quality adhesives and mortars that are compliant with ASTM C1714/C1714M standards.

The case of the Orlando City Stadium, for instance, exemplifies the importance of attention to detail. Despite Florida’s heavy rainfall and intense sun, the MSV installation remains in excellent condition due to careful planning and execution of the detailing and installation requirements, especially the area’s propensity for thermal expansion and frequent storms.

Code Requirements and ASTM Standards Applicability

Understanding the applicability of code requirements and ASTM standards is vital. For instance, ASTM standards may prescribe the compressive strength of the mortar, but local codes might dictate additional water penetration resistance requirements due to regional weather patterns. In the Southeast, it is not uncommon for local codes to require additional testing or certifications due to the region’s vulnerability to severe weather.

For professionals in the architectural and construction fields, mastery over the components and requirements of MSV systems is non-negotiable. In the Southeast, this expertise must be contextualized within the regional peculiarities of climate and local building customs. From the coastal vicissitudes of Florida to the historical sensitivities of South Carolina, each application of MSV must be thoughtfully considered and meticulously executed.

Knowledge of MSV systems provides architects and contractors with the technical foundation to create durable, beautiful, and code-compliant structures. With a firm grasp on building codes, ASTM standards, and industry recommendations, professionals can ensure that their use of MSV not only enhances the aesthetic value of their projects but also upholds the integrity and longevity that the industry and the inhabitants of the Southeast region deserve.