Effects of Climate on EIFS Exterior Finishes

Exterior Insulation and Finish Systems, popularly known as “EIFS”, is an exterior building cladding system designed decades ago to provide energy efficiency with integrated layers of various composite materials. Designed to act as a winter coat for any structure, the EIFS system is more than a simple exterior layer intended to add aesthetic value and protection.

From the inside outward, EIFS exterior finishes typically consists of a gypsum board interior surface covering a cavity insulation material, a sheathing material, a drainage plane of felt or housewrap, a drainage cavity with spacers to release trapped moisture, and finally a synthetic or traditional stucco applied over rigid insulation. These layers serve to eliminate energy transfer between the inside and outside while draining any moisture that is prone to accumulate when heat meets cold. 

Modern EIFS, with the addition of the moisture-eliminating cavity and materials, are called Drained EIFS.

How Do Climate Changes Affect Drained EIFS?

According to a Building Science blog from July 2007, many of the EIFS claddings installed in the 1980’s in humid or semi-humid areas eventually developed moisture accumulation problems. The result would be excess mold, decay, fungi, and deterioration. The problem was a result of moisture trapped between the layers and very limited drying potential in those areas.

 More recent variations of EIFS exterior finishes have eliminated the problem by designing drained EIFS that incorporate moisture eliminating cavities and barriers. As a result, accumulated moisture is no longer a problem with properly installed, energy-efficient EIFS.

The key to eliminating all moisture problems is to design and construct the exterior system in which the drying capability is greater than the wetting potential, i.e. rain. To minimize the impact of precipitation on any cladding surface, including EIFS, architects add features to redirect or channel water away from the exterior surface. In any event, in climates where rainfall is normal or above, drained EIFS systems are far superior to the original surface EIFS that were intended strictly to reduce energy costs.

Water Control Measures

In areas like the Southeast or Pacific Northwest where rain can be abundant, architects employ three approaches to prevent damage due from water accumulation. These are:

●       Draining configurations like drained EIFS with built-in moisture eliminating cavities.

●       Water-stored, as in reservoirs in brick, stone, masonry or concrete structures in which absorbed moisture dries through capillary action.

●       Perfect Barrier approach in which the surface cladding is “face sealed” or is built with an interior barrier known as a “concealed barrier.”

Contact ProCoat Systems of Denver

For more information about drained EIFS, energy saving, and other cladding options, phone the experts at ProCoat at 303.322.9009.

Or, visit their website at http://www.procoatsystems.com/ to learn more.

This post was originally published at http://www.procoatsystems.com/effects-climate-eifs-exterior-finishes/