ATLANTA - Hardcoat stucco siding is a siding material made of Portland cement, sand, lime, and water. Applied in three coats over a lath base, it provides a solid, durable, and seamless home exterior. Some advantages of hardcoat stucco include a natural resistance to fire, lasting durability, and low maintenance. It is labor0-intensive and thus very expensive.
Synthetic stucco is commonly referred to as Exterior Insulating and Finish System (EIFS). Homes with this exterior finish are often strikingly beautiful, offer great flexibility in home design, and provide energy savings. The process originated in Atlanta in 1980, and quickly became popular in higher-end homes, used in almost 30% of homes built in the southeast by the early 90’s.
EIFS (usually pronounced “eefs”) constructed homes, however, have a dark cloud surrounding them - allegations of water accumulation and damage resulting in mold growth.
EIFS construction consists of an insulation board secured to the exterior wall surface (e.g., plywood), a durable, water-resistant base coat applied on top of the insulation and reinforced with fiberglass mesh, and a finish coat, which gives the product its stucco-like appearance.
The moisture intrusion controversy erupted in 1995, with several EIFS-related lawsuits. Homeowners alleged the following:
- Increased level of humidity within the home
- Infestations of termites, ants, and other insects
- Mold, mildew, or fungus growing on the interior walls or on window frames
- Cracking of the drywall
- Cracking, peeling, and bubbling of paint
- Cracking on the EIFS dressing bands around windows
- Delamination—EIFS coming loose from the sheathing of the house
- Rotting of wood trim
- Loss of structural integrity
Growing evidence suggested that once water got into the EIFS insulation board, it had no way of getting out. Thus, water penetration is not the problem itself, as water can easily penetrate many types of exterior finishes, such as wood and brick.
The problem is, according to some civil engineers, water retention. The original EIFS system virtually wraps the exterior of the home in an energy-efficient blanket, which promotes energy efficiency, but can leave water trapped within.
This product cannot breathe. It collects moisture, and the moisture has no way to drain or evaporate.
To counteract these problems, the EIFS industry developed a more drainable type of exterior finish in the last few years. The new “drainable” or “water-managed” system incorporates a secondary moisture barrier and a drainage mat with weep holes in the bottom that allow the escape of water that might get trapped.
I have become convinced that the new system, including installation of a water drainage system, is an outstanding surface. Today, the problem is not the product, it’s the public perception among consumers. So many owners were burned by poorly installed synthetic stucco, that most buyers today won’t even CONSIDER buying a home built with the EIFS system.
Synthetic stucco has all but disappeared from residential construction. Any stucco you see on a new home is probably cement-based hard-coat.
THE BOTTOM LINE: I hate to say this, but this is a case where the perception becomes the reality. I can’t recommend this exterior cladding because it is likely going to be very hard to sell when the time comes.