Development & History
Exterior Insulated Finishing System (EIFS) is a wall finish system developed in Europe during the rebuilding
process following World War II. It was designed as a finishing system for the
exterior of buildings. The driving goal was to develop an efficient way to
manage energy inside a building when the insulation is added to the exterior.
By maintaining the wall at a more even temperature there would be less wall
movement due to expansion, contraction, and heat loss. The result would be a
building that would retain heat, reducing the energy demand during peak
heating and cooling periods. In accomplishing this goal it was determined that
placing the insulation on the exterior was most efficient since the bulk of
the structures in Europe are some form of masonry with no hollow wall
German scientists formulated a variety of materials utilizing polymer
chemistry. Utilizing this technology they designed a cladding that would be
efficient at protecting the insulation from the elements, while maintaining a
pleasing appearance. The end result is an exterior polystyrene insulation foam
board that uses an adhesive to hold the board in place and a flexible
synthetic plaster coating added to the surface as a protectant. The insulation
boards would be protected yet the finish would be able to expand and contract
with the weather extremes. This cladding material is designed to be a finish
system only. It provides no structural support.
HOW SERIOUS IS SERIOUS?
How serious is the problem? A National Residential Relocation and Environmental Inspection Company on May 4th, 1998, stated
that over the
previous 10 months they conducted well over 400 Synthetic Stucco inspections and have found varying
degrees of damage on all but one home. The moisture penetration they uncovered and the resulting damage
had been as high as $100,000 on a home with a
market value of $450,000.
extensive is the use of EIFS? The same relocation company stated that "
EIFS has been applied to 250,000 homes in the US, and that number is growing at
a rate of 10% per year.
According to a study commissioned by the NAHB (National Association of Home Builders), homes surveyed "ages two to six are experiencing structural damage due to excessive moisture buildup within walls. The cause of moisture accumulation is rain water intrusion from a combination of factors including: improper sealing at joints and around windows, doors and other penetrations; improperly sloped horizontal EIFS surfaces; inadequate flashing at roof lines, dormers, decks, fireplace chases etc.; and window frames that leak into wall cavities_" Moisture buildup and rotting was found to be insidious as it could not be determined from visual inspection. EIFS is designed to be a face-sealed barrier providing a weatherproof membrane. All water shed at the outermost surface of the EIFS lamina since water entering behind the base coat can enter the wall cavity. Therefore, watertight sealing around penetrations such as windows, doors, electrical outlets, vents, roofing, etc., is essential to maintaining the integrity of the EIFS. Moisture readings ranged from 18% to greater than 50% in sheathing near band joists below window and door openings."