Choosing an Installation System for Your Metal Composite Cladding
ALPOLIC® has been an innovation leader in metal composite materials for decades and is the clear choice for architectural cladding because of its unsurpassed variety of colors, durability, and adaptability. However, our MCM products are just one part of the decision process when designing a building envelope. When it comes to selecting a cladding system, it is important to understand the options.
Cladding systems fall into one of two general categories, sealed and rainscreen, and there are multiple factors that should be evaluated when determining the ideal cladding system for your specific project. Some considerations include: the project environment, aesthetic needs, wall performance and code requirements as well as the project budget.
Sealed systems are designed to create an outward layer of protection against the elements with water-resistant cladding and sealed joints. Two common examples of sealed systems are referred to as wet seal, a system sealed with caulk and backer rod, or dry seal, a system with gaskets and/or filler strip. The water-tight barrier depends greatly on the effective application of the joint seal, which should receive regular inspection and maintenance.
Rainscreen systems, do not rely on a single face-seal approach, but rather manage wind and water intrusion in a two-layer system. Most of the water intrusion is managed in the outer cladding layer, but an interior air water barrier (AWB) is required as a second line of defense. We’ll compare two common rainscreen systems that manage water intrusion differently.
A Pressure Equalized Rainscreen (PER) system works on the basic premise that if there is equal pressure between the interior cavity of the system and the environment outside the cladding barrier, there will be no water intrusion. Pressure is regulated by engineering separate compartments behind the cladding, restricting for air flow. Pressure equalization works in conjunction with drainage and drying capability to present an efficient system for managing moisture.
The focus of a Drained and Back Ventilated Rainscreen (DBVR) system isn’t to stop water intrusion through pressure, but rather to create a system to drain and dry any water that does enter the cavity with a design that facilitates water drainage and air ventilation.
Architectural Testing, Inc. (ATI) released an Informational Bulletin detailing the American Architectural Manufacturers Association (AAMA) testing methods for rainscreen wall cladding systems. AAMA 508 measures the performance of PER Systems on pass/fail criteria. AAMA 509 measures the performance of DBVR systems on a classification system that measures moisture accumulation down the AWB as well as the capacity for air to circulate. The results are plotted on a chart and the “W-V” classification is used to allow comparison between 509 systems.
Architects, fabricators and installers must select the system that meets their design and performance requirements. ALPOLIC® frequently collaborates with these industry stakeholders to find solutions to unique challenges, such as designing an installation system capable of withstanding hurricane-force winds. A member of the Metal Construction Association (MCA), ALPOLIC® is proud to be in the vanguard of industry, collaborating with a network of fabricators to ensure our products are integrated into a building envelope effectively. For additional reference, MCA released a Technical Bulletin defining basic installation systems in greater detail.
As designers explore new techniques with our versatile product, many are creating their own systems for installation, producing some inspiring designs. Whether sealed, rainscreen or custom fabricated, we’ll work together to realize your design in a system that will combine beauty with function. A properly designed installation system incorporating ALPOLIC® metal composite materials can create a building envelope that is resistant to wind and rain, improves energy efficiency and allows for uniquely creative visual appeal.
For additional installation detail drawings and industry information, visit our Technical Resources page.