Issue link: http://cp.revolio.com/i/399448
EIFS "outperformed all other walls in terms of moisture while maintaining superior thermal performance". That's what the researchers at Oak Ridge National Laboratory (ORNL) said about walls made of exterior insulation finishing systems (EIFS) – a wall cladding system made with expanded polystyrene foam insulation - in their three-part study conducted on behalf of the U.S. Department of Energy (DOE). Simply stated, the report proves EIFS perform better than other exterior claddings. Based on this real world study, The Hygrothermal Performance of the Net Exterior Insulation Walls, EIFS are an outstanding exterior cladding choice to achieve several key building performance goals, including energy efficiency, temperature control and moisture control. Results show that unlike traditional claddings such as brick and stucco EIFS do not absorb moisture or retain heat. Additionally, EIFS control the heat flow in a building more efficiently. Testing was conducted over an extended period of time on a building constructed near Charleston, South Carolina, a mixed, coastal zone 3 climate that featured exterior wall panels made from various claddings and assemblies. Each panel was fitted with a sensor that provided a full profile of temperature, heat flux, relative humidity and moisture content values. Data was collected 24 hours a day and transmitted to the ORNL research facility in Oak Ridge, Tennessee, where it was extensively analyzed. The data was collected in two phases; the goal was to have all of the claddings exposed to similar weather conditions for a year to represent common environmental challenges such as moisture and temperature swings. Phase I of the study was composed of 15 exterior cladding configurations integrated into one side of the building. In Phase II, researchers simulated building envelope defects to assess (1) the performance of cladding assemblies to water penetration, (2) the effect of wall orientation on moisture infiltration and its impact on the performance of wall systems and (3) types of water-resistive barriers(e.g. sheet barriers versus liquid applied) and different exterior cladding systems used (e.g., EIFS, brick). The hygrothermal performance (i.e. temperature and moisture control) was evaluated for three EIFS including: 1. Liquid-applied water-resistive barrier coatings that handle rainwater penetration or condensation due to vapor pressure gradient changes. 2. Ventilated exterior claddings intentionally ventilated (open at top and bottom) and drained to allow air to move freely behind the cladding and increase drying potential. The EIFS wall absorbed little moisture and maintained a consistent, acceptable moisture level within the cladding despite varying outdoor conditions. The research to investigate the side-by-side performances of each wall cladding system— the field data and the hygrothermal model derived from it— allows architects and engineers to optimize energy efficiency while controlling air and moisture transport. Energy Efficient Building with EIFS Newsline issue 5 | fall 2014 Advance innovative EPS product solutions that contribute to a sustainable future 1298 Cronson Blvd. • Suite 201 • Crofton, MD 21114 • (800) 607-3772 • www.epsindustry.org • info@epsindustry.org SUSTAINABILITY 3 PACKAGING 5 TECH TALK 7 INNOVATION 12