While stucco is more vulnerable to moisture infiltration than other siding materials, many developers relied extensively on the plaster during the building boom that took hold nearly 30 years ago. Stucco was particularly popular in “luxury” developments. The material is more expensive per square foot than vinyl or wood, but far less labor-intensive than brick or stone. It was a middle-ground option, allowing home builders to advertise “quality” properties while keeping profit margins high.

Stucco Homes “Fail” At Alarming Rates

As many communities have discovered, stucco becomes an inappropriate housing choice when paired with low-quality construction. Critics have gone even further, suggesting that stucco just isn’t compatible with the way walls are being built anymore.

Stucco Wall

Developments in southeastern Pennsylvania have been particularly hard-hit, with stucco and mold remediation efforts beginning on thousands of homes around Philadelphia over the last few years. Many families have been left facing repair bills well over $150,000. Some have chosen to file stucco lawsuits, accusing developers and contractors of selling sub-standard homes at exorbitant prices.

Stucco Water Damage Reported Country-wide

Pennsylvania isn’t the only place where widespread stucco damage has been attributed to careless construction choices. Stucco homes in Minnesota have also had a “nasty history of catastrophic failures,” according to Reuben Saltzman, a home inspector based in Minneapolis.

In Twin Cities-suburb Blaine, Saltzman has seen entire developments undergoing full stucco remediation – all to repair moisture intrusion.

Woodbury, MN: A Case Study

To the surprise of many, a small suburb of Minneapolis has come to play a central role in unveiling, and tackling, the widespread stucco water damage impacting numerous homes across the country.

In 1999, Woodbury, Minessota’s Building Inspection Division found that 26% out of 670 stucco homes displayed “visible signs of moisture damage.” The vast majority of these homes had been built within a decade of the city’s initial review. “Leaks and major structural damage” were becoming apparent throughout Woodbury’s stucco home stock, even though the homes had only been standing for a few years.

4 Construction Factors Behind Stucco Failures

Searching for answers, city inspectors thoroughly evaluated every home undergoing repair, ultimately identifying four major factors contributing to the water damage:

  1. Window leaks
  2. Lack of kickout flashing – Kickout flashing channels water into gutters, preventing moisture from infiltrating the cladding where a home’s roof meets exterior walls. Installed properly, kickout flashing provides superior protection against water penetration. Recent increases in the use of insulation and building wrap, which inhibit air circulation within a home’s envelope, have made kickout flashing a must in residential construction.
  3. Improper deck flashing – A deck’s ledger board should never be nailed directly to the house. Instead, metal or membrane flashings need to be installed first, which will direct rainwater to the ground rather than into the home’s sheathing.
  4. Grade above wood framing – Installed below ground, stucco can prevent trapped moisture from draining properly or draw water upwards into framing.

Later the same year, Woodbury went public with its stucco problem, holding meetings with contractors and municipal building inspectors, along with Minnesota’s state-level Building Codes and Standards Division. Stucco regulation changes came soon after, including a mandatory inspection process for all newly-constructed stucco homes. Despite these efforts, the city’s battle against low-quality stucco construction isn’t over yet.

Despite City Efforts, Stucco Homes In Minnesota Continue To Crumble

While the local construction industry opted to update its stucco installation methods, new homes continue to show “unacceptable failure rate[s].” The most promising upgrades, like drainage planes, are still rarely used.

Recent analysis shows that Woodbury’s stucco homes are still degrading. As of 2011, more than 67% of the city’s stucco-clad homes had failed and undergone repairs. 53 of the homes have required multiple rounds of remediation. On average, a stucco home will only last 8.7 years after construction before requiring repairs. The city’s Building Inspection Division has now openly “question[ed] the viability of stucco on current wall systems.”

In Woodbury, as in may parts of southeastern Pennsylvania, there is strong evidence to suggest that faulty construction is at the root of stucco water damage. In fact, cheap, inappropriate stucco installation methods seem to have become industry standard in the 1980s and 1990s. The problem doesn’t begin and end in Minnesota and Pennsylvania. According to Woodbury’s conversations with key stakeholders, major stucco issues impact homes across the nation.