INFORMATION  - Synthetic Stucco Cladding is the Best Cladding for any Home

What is the best cladding for a home buyer to build with or buy? Is there really a "best cladding"? Would you believe that a synthetic stucco clad house is the best by any standard of measurement and behavior? How can it be superior to brick, cedar, wood lap, vinyl siding, and hard coat stucco?

Let me tell you how. Until 1995, all house claddings were essentially considered about equal by the general population and code authorities, with little thought given to weather-resistance and structural capability of the cladding. Claddings were chosen by builders, homeowners, architects, and building designers on personal appeal and economy. In 1995, structural deterioration started to enter the marketplace with the discovery of water penetration behind the stucco in the Wilmington, North Carolina area. A mild panic developed with respect to the use of synthetic stucco as an exterior cladding. Conclusions were erroneously made very quickly that a synthetic stucco house was a poor exterior cladding, because it was a barrier system and wouldn't let any water that entered the wall cavity dry out without rot developing. It was further assumed that other claddings, like brick, cedar shingles, lap wood, vinyl sidings, and hard coat stucco were not barrier system and that they let water that entered the wall cavity dry out without rot developing. The conclusion was made that brick, cedar shingles, lap wood, vinyl sidings, and hard coat stucco were superior to synthetic stucco because they were not barrier systems, but were so-called "ventilating systems".

People starting asking the question, "Why is this wet cavity problem just developing?" Houses have been built for centuries and this question never developed. Now with synthetic stucco it was a major problem. Why didn't brick and the other claddings have this problem?

The answer is very simple - The other claddings "do" have rot problems. There are almost no other clad houses that don't have serious band rot at decks, patios, and landings around the perimeter of the house, as well as window leakage.

Our firm has conducted thousands of inspections of existing houses as old as 100 years and of all types and descriptions, and in almost every inspection you can expect to find band rot at decks, patios, and landings where they are exposed to the weather. The reason is that most houses were not flashed properly in these areas to protect the bands and prevent rot, but these rot conditions were not discovered until an inspection was made. Wall cavities are never inspected unless the brick is removed.

Leakage due to window construction and caulking or lack of caulking has generally never been inspected on brick and other clad houses, but in the few houses where these sidings have been removed for whatever reason, leakage at windows due to internal construction, poor caulking, or lack of caulking is evident, with rot present in most cases.

In many brick and sidings other than stucco, termite and ant infestation is also often evident. Older houses where brick and the other sidings are removed have rot of framing present in almost all cases. Again, this rot isn't evident until some intrusive openings or inspections are made in the cladding.

Now, to answer the question, "Why no publicity about wet framing in brick, hard coat stucco, and other claddings other than synthetic stucco?" The answer is simple; no inspections have been made on the claddings other than synthetic stucco, because it is difficult to test the wall cavities of these other claddings. It is easy to test synthetic stucco without serious, costly, intrusive inspections. Because of this ease of inspections, wet conditions are readily determined, whereas in brick, hard coat stucco, and other claddings it is difficult and expensive to inspect the framing of a house. As such, no inspections are generally made on the "assumed condition" that because there is no evidence of water intrusion and damage, "none will exist." This is a very erroneous assumption and is not justified by our thousands of inspections of houses other than synthetic stucco houses. Underlying all of these apparent problems with synthetic stucco is the concept that if leaks develop in the wall cavity and rot develops, the house is going to collapse. Houses don't collapse from rotted framing or rotted windows. They are structurally very adaptive to the loss of some framing due to rot.

Recently, we inspected a cedar shingle house that was over 70 years old. It looked perfectly good, but some termites were seen; and the lower level siding was removed to determine the extent of the termite damage. The removal process started at one corner where the termites first were noticed, but it continued until the entire perimeter was exposed and, "Guess what was seen?" The bands were almost completely rotted, either from water intrusion or from termite infestation. Three of the main corner stud constructions were completely rotted from water intrusion over the years. This wasn't seen by any of the owners and occupants of the house, and the house didn't collapse. The house wasn't inspected because it was difficult to inspect and would have been very costly to inspect, because no damage was readily visible.

In early 1998, we inspected a new brick home that was only two years old, but every window was rotting and decaying due to water intrusion in between the glass and rabbets. No stucco was on the house, only brick. Poor internal construction of the windows was the culprit.

As we review our inspections of non-stucco homes and stucco homes, the very same causes of water intrusion are present in all houses, regardless of the cladding used. They are as follows:
  • Poor or no flashings at critical locations
  • Poor internal window construction
  • Poor caulking or lack of caulking.
We don't find much wrong with any of the claddings themselves, including synthetic stucco. There will always be some defects in all claddings. Some common defects are as follows:
  • Brick - No or only partial mortar in some joints, poor mortar strength, cracked brick, lack of caulking, or poor caulking.
  • Sidings of Wood and Vinyl - Insufficient anchors, no provision or inadequate provision for movement, broken or damaged pieces, lack of caulking, or poor caulking.
  • Hard Coat Stucco - Poor strength, insufficient metal lath, missing accessories, too large of areas between expansion joints, excessive cracking, and lack of caulking or poor caulking.
  • Synthetic Stucco - Gaps in insulation board, reinforcing mesh showing, flat top details, lack of caulking or poor caulking
Now, why is synthetic stucco the best cladding for any house? It is quite elementary. With all of the problems of the past three years, it has become easy to economically test and evaluate the entire synthetic stucco house, whereas it is almost impossible to test and evaluate all of the other claddings easily and economically. It is easy to repair the window constructions, correct the flashings, and properly caulk. You can and "positively inspect and know" that your synthetic stucco house is in good, dry condition, "without guesswork". This can't be done with other claddings. With yearly inspections and maintenance, your synthetic stucco house "will not" have hidden rot, as you can expect from any brick or other cladding house.

Therefore, "A SYNTHETIC HOUSE CAN BE PROPERLY AND ECONOMICALLY MAINTAINED OVER ITS LIFE, RESULTING IN THE BEST CLAD HOUSE THAT YOU CAN BUILD OR BUY." You can know that your synthetic stucco house is dry, whereas you cannot know this with other claddings, thus making synthetic stucco the best cladding for any house.

Success in any endeavor is based upon the vehicle of "KNOWLEDGE". With a synthetic stucco house, you have this vehicle of knowledge of your home's condition. On all other houses clad in materials different from synthetic stucco, you don't have the knowledge vehicle to understand positively that your home is dry, rot and termite free. Synthetic Stucco Is the best cladding you can have for your home!

* Peter J. Verna, Jr. is a registered, professional structural engineer in several states, a graduate of Cornell University with over 50 years design and construction experience, which included management of a large, national construction firm, extensive ready-mix concrete and precast, prestressed concrete operations. His firms, Verna and Associates, Inc. and Verna Engineering, P.C. currently specialize in structural, residential and commercial design; broad general structural inspections; stucco inspections; special structural repairs; stucco repairs; and forensic and expert witness work.