Larger, thicker panels may be required to handle dramatic temperature changes in extreme climates and strong wind loads. For example, extruded concrete panels are relatively lightweight and can easily be mounted. One of the main considerations is panel size and thickness, and how those dimensions work to meet a building’s needs. Weight: Material weight is a huge issue for both the shipping of materials to the project site and the installation. However, fiberboard is not commonly used for siding because of its low fire-resistant properties. Water mitigation: Fiberboard, cement board, cast-in-place concrete, and extruded concrete are all highly moisture resistant. Here’s how the various materials compare.
From an architectural standpoint, they also need some level of design flexibility.Ĭommonly used materials include fiberboard, cement board, cast-in-place concrete, and extruded concrete. The trade-off with various materials, however, is that they need to balance water mitigation with weight, strength, and overall durability. Some materials, such as ceramic tile or different metals, may have a high gloss that can help water shear away from the surface. Ideally, the material will deflect water from the building surface or, if somewhat porous, will distribute and dry the moisture before it enters the air cavity. The physical characteristics of exterior rainscreen cladding tend to follow the four Ds carefully, but with a strong emphasis on the durability. Regardless of the rainscreen design, a good rainscreen needs to meet the “ four Ds”: deflect water, drain moisture, dry any water that has penetrated the cladding, and be durable enough to withstand the elements over time without deteriorating. Some systems work to force air through the wall cavity/air gap to equalize the pressure between the exterior and interior wall, thus preventing any moisture from entering. The goal of a rainscreen is to prevent moisture from entering the building shell, but also to provide an internal means of water drainage and evaporation if water does get through. Physical Attributes, Benefits, and Challenges of Typical Rainscreen Material