Traditional Rendering Versus Slipfaced
The exterior insulation finish system or EIFS was all the rage when service people returned from World War 2. There was a great surge to modernise old buildings, however plastering stucco over was expensive, and many craftspeople had been lost in battle.
Then somebody hit on the idea of covering exterior walls with boards and plastering over them lightly. This method required a lesser skill because the surface was already smooth.
Unfortunately the original system was not as robust as genuine stucco, and there were water infiltration problems.
EIFS Exterior Insulation Finish Systems from the Mid-1960’s
EIFS was all the rage in 1960’s North America. Exterior insulation evolved into an insulated, water-resistant, finished surface that appeared to prevent water penetration.
The new system initially appeared on masonry buildings, however by the 1990’s most upgrades were on wood-frame buildings.But there was still no internal drainage in the event water did find its way through.
How High-Profile Problems Developed in the 1980’s
Water leakage was found in several high-profile projects. Lawyers had a field day when the ‘leaky condo crisis’ erupted in Southwest British Columbia. Something similar happened in New Zealand during the ‘leaky homes crisis’.
The problems in New Zealand revolved around damp timber rotting behind the cladding rendering some homes dangerous. Whereas in Southwest British Columbia the exterior covering decayed, with consequential mold and spores inside the walls and building interior.
Homeowners faced huge repair bills, fixing a problem they did not create often caused by a contractor they did not engage.
They faced financial hardship if they purchased the units from a previous owner, their developer, or their developer/contractor to whom they had no recourse.
Extent of the Southwest British Columbia Leaky Condo Crisis
The historic statistics are striking. Close to 46% of 159,979 condominium strata units constructed in B.C. between 1985 and 2000 developed envelope leak problems. Moreover, 57% of the 700 school buildings suffered similarly.
A provincial commission of inquiry blamed numerous factors, including
# Design features inappropriate for our climate
# Reliance on face-sealed wall systems
# Fundamental lack of awareness regarding enclosure
# Lack of meaningful inspection at critical stages of construction
# A regulatory system which was unable to cope with the failures
So Does That Mean the EIFS System Is Dead?
No not at all. The EIFS industry has always claimed those problems were the result of poor workmanship, and not fundamentally flawed system .
Homeowners now have two systems from which to choose, namely Class PB polymer-based, and Class PM polymer-modified exterior insulation finished systems.
The best ones have drainage cavities behind the system to drain away any moisture that does penetrate. Therefore, there is no reason not to consider a modern EIFS system.
However, Valiant Exteriors believes it is a wise idea to check with your insurer first before modifying your home . Especially if this is to the roof or exterior walls, your primary defenses against extreme weather.