A new document produced by CLAPCA attempts to offer the last word on moisture intrusion.

The Carolinas Lathing and Plastering Contractors Association began with a small group of plastering contractors during what was, without question, the darkest time for both product manufacturers and plastering tradespeople alike. That time began in mid to early 1995, when the construction industry began to hear of moisture-related problems associated with EIFS-cladded structures.

With little knowledge of what the true cause of these problems were, both the product manufacturers and the plastering industry were charged as responsible and found to be guilty as charged. Over the next year or so, it became obvious that the real problems rarely related to product or installation problems, but to construction errors, such as the lack of proper flashing details, sealants, and defective windows and doors that were found to be leaking internally.

These same product and construction errors, which have proved to affect all structures, have equally affected structures cladded with conventional or hard-coat stucco, and like the attack on EIFS, likely due to their similarity, a similar attack is now arising against those structures clad with hard-coat stucco.

The wheat from the chaff

CLAPCA has developed a position paper through its technical committee that provides an industry standard for evaluating and providing repair protocol on existing hard-coat stucco systems. The position paper is offered by CLAPCA as a guide for inspection and evaluation of stucco for building owners, lenders, inspectors and prospective buyers. The premise is that existing stucco that is functional—even though the stucco and other components of the wall assembly may not be installed in accordance with building codes, ASTM or other industry standards or locally accepted practices—does not necessarily require remediation or complete replacement to continue to be a viable water-resistant cladding.

The position paper discusses both conditions related to builder responsibility, as well as plastering contractors’ responsibilities. It provides information relating to the accepted method for evaluating such components as structure substrate or stucco backing materials, weather barrier, lath attachment, stucco thickness, control joints, and flashing and sealant, as well as the use of acrylic stucco finishes.

The position paper is designed to be useful as an instrument that does not only standardize the inspection procedures but also helps inspectors, builders, applicators, home buyers and sellers better understand the system components. It provides information on how one can responsibly evaluate stucco on a case-by-case basis that deals with the real problems that affect the ability of the stucco along with related components to function as an overall effective protective surface.

The paper reads: “Generally, stucco installed on residences prior to 1998 are installed without a weather barrier. Of those that do have a weather barrier, the weather barrier may not be functional because of installation errors.

“The simple determination of the existence or non-existence or functionality of a weather barrier is therefore not an acceptable determination as to the ability of an existing stucco application to provide protection against moisture infiltration.”

As an inspector experienced in envelopes, I personally believe that inspection reports that are not based on individual merit, without demonstrating how the violation has or likely will ever become a problem, are not responsible and potentially injurious to builders, applicators, home buyers and sellers, among others.

For example, inspection reports that make issue over the lack of a detectable barrier material are inappropriate unless identifiable problems associated with the lack of the barrier are detectable as well. Understanding the vast majority of stucco installed on residential structures in the east is installed without weather barrier material, it would be irresponsible to condemn all or any of these homes without some detectable evidence of a problem associated with the lack of a barrier.

Additionally, since evaluations that note the existence of a barrier have no non-intrusive method of determining how the barrier was installed, they also can be misleading in that the inspector has no way of determining if it was even installed as a functional barrier.

Another example would be inspection reports that identify the lack of, or improper, installation of control joints, and requires them to be retrofit into an existing system without identifying any justifiable reason other than that they were missing. Understanding the alleged technical reasons for installing control joints, and the controversy between experts who cannot agree on how, where and why there is a need for control joints, the position paper takes the logical approach that states: “No remediation or retrofitting should be recommended unless an identifiable problem has been detected that would be resolved through the installation of a control joint.”

Shelter from the code

As a licensed general contractor in both California and North Carolina, and a licensed building inspector in North Carolina, I have worked in more than 12 states and have in excess of 30 years of experience in the construction industry. I have spent the last six years inspecting more than 2,000 structures solely for the purpose of evaluating them from the standpoint of barrier or protective siding application. I sat as a member on the Mecklenburg County, N.C., Stucco Task Force and currently am a member of the CLAPCA Technical Committee.

As an inspector, I believe the primary purpose of an evaluation should be to assess the condition and functionality of the exterior siding materials and related components to function for the purpose of providing protection to the structure against damaging weather elements. The objective of the evaluation should be to determine existing or potential sources of moisture infiltration, the extent of damage that may have occurred, the cause or source of the infiltration, and the protocol for repair. The evaluation does not reflect on code compliance, ASTM standards, or what one believes to be industry standard unless there is evidence the lack of a standard causes the problem.

We believe evaluations based solely on these standards typically require costly repairs, do not improve the ability of the stucco to perform its intended purpose and, very often, do not resolve any of the real problems.

Providing inspection reports that are based solely upon code standards is simple to do. It only requires that one knows the codes. It’s quite another thing to understand the function of each component of an existing stucco application and how those components interact with one another within a given structure, and to provide information that responsibly identifies and resolves the problems.

The position paper, now available through CLAPCA, is a tool that can be used to help better understand stucco applications, as well as provide productive and effective evaluation reports.

When considering the problems we have experienced, it is important to understand that stucco has historically proved itself to be a viable exterior cladding material. It has successfully provided protection to structures for more than a thousand years, and will continue to do so in the future.

Knowing this, one should ask: How can a product that has successfully functioned for the period stucco has, suddenly fail in the last eight to 10 years? The answer is that it is not the stucco!