Today’s adhered masonry veneer walls are typically more vulnerable to moisture problems than older “thick mass” masonry walls or today’s masonry cavity walls. The reason is simple – most of today’s typical masonry veneer walls are built without a space between the veneer and the substrate, so they don’t allow fast and complete drainage and drying behind the veneer. The traditional method of using two layers of building paper between the substrate and scratch coat may provide some drainage, but it doesn’t allow ventilation and it won’t prevent mortar bridging.
Since the characteristics of moisture movement in veneer walls are the same as those of masonry cavity walls, it only makes sense to provide the equivalent of a cavity behind the adhered veneer. Without this cavity, often called a “drainage/ventilation plane” in adhered masonry walls, mortar bridging between the veneer and substrate can occur, which can conduct infiltrating water from the veneer to the substrate. In addition, without a drainage/ventilation plane behind the veneer, there is no way for air to circulate and dry the veneer or the substrate. Veneers, mortar, cracks and flashing failures will allow moisture into the wall, and without a drainage/ventilation plane, it can damage moisture-sensitive wall components.
As a result, the need for efficient drainage and rapid, complete drying are important considerations when designing and installing adhered masonry veneers.
Moisture Intrusion Problems
When moisture can’t dry behind an adhered masonry wall system, the consequences range from merely inconvenient to very expensive, plus wall failure can seriously damage a builder’s reputation. They include:
Let’s examine each of these potential problems in greater detail:
Mold growth – Insulation, sheathing, drywall and any wall materials with organic content are vulnerable to mold infestation resulting from moisture trapped in walls. Mold remediation is often an expensive and complicated process requiring professional expertise, and extensive mold infestations can lead to lawsuits that can damage a contractor’s reputation. Affected areas must be sealed off to minimize spore dispersion, and it is necessary to completely remove and replace affected wall components.
Chronic efflorescence – Efflorescence is the white powder that results from minerals in the mortar migrating to the exterior surface of the masonry veneer. Chronic efflorescence is caused by there being more moisture inside the wall than in the outside air. This causes the moisture to migrate through the mortar and results in a continuing cycle of mineral stains, surface cleansing and more mineral stains. While efflorescence doesn’t cause structural damage, it is unsightly, requires ongoing maintenance and will definitely create an unhappy customer.
Excessive humidity – Too much moisture in the air encourages bacterial growth, and relative humidity inside the walls of greater than 60% can feed mold growth, which may compromise interior air quality. When excess humidity infiltrates walls, interior humidity levels rise. This often increases the amount of heating and cooling required to maintain the comfort of occupants.
Deteriorating metal components – If the metal lath used for the scratch coat rusts, the rust will expand and may create cracks and even push the veneer off the wall. The metal fasteners used to adhere the masonry veneer to the structural substrate may also rust or corrode and eventually fail, and if the veneer pulls away from the substrate, it not only creates the opportunity for more water damage but can also injure people and damage property if it falls without warning.
Cracking and spalling – Excess moisture which migrates to the wall’s surface may lead to cracking and spalling, which can allow more moisture behind the wall, creating a vicious cycle of water damage leading to more water damage. Widespread deterioration may also have an adverse impact on leasing, and will almost certainly decrease a property’s value.
Unfortunately, moisture damage behind adhered masonry veneers may remain hidden for months or years before it becomes obvious, and by that time, repairs may be very expensive, sometimes reaching into the tens of thousands of dollars. Money spent on prevention of moisture problems will always be a good investment and is likely to pay for itself multiple times during the building’s life.
Of course, it is best to design moisture management into the wall to prevent damage rather than try to fix the wall once moisture has damaged it.. A properly designed wall will include:
Drainage/ventilation planes – A plastic mesh drainage/ventilation plane at least ¼” thick should be installed continuously behind the adhered veneer to allow drainage and airflow vital to managing moisture in the wall. The continuous mesh acts as a mortar break to prevent bridging, and moisture that does get behind the veneer travels to the bottom of the wall where it escapes through openings in the weep screed. The mesh also allows air circulation to promote rapid drying. Modern substrates are designed to withstand occasional wetting without damage, but if a substrate and other wall components never dry completely, mold and structural problems will result.
Weep screeds – Weep screeds are often used at the bottom of adhered masonry walls to provide a clean termination line for the veneer. While a weep screed has holes for drainage and ventilation, they are not considered to be weep holes as the term is used in masonry cavity walls. However, like weep holes, the weep screed holes provide a means for the moisture that flows down the drainage/ventilation plane to exit the wall and they provide a way for air to move into the drainage/ventilation plane to dry the wall components and the veneer from the back.
Moisture damage is the leading cause of masonry building failure – it can cost big dollars to fix and ruin a contractor’s reputation. Mortar Net Solutions is the industry leader in masonry moisture management, and DriPlane and LathNet are two solutions designed specifically to provide the drainage and ventilation plane vital to adhered masonry wall sustainability and beauty. Click here to find a distributor near you. Click here for free samples. For additional information, please contact us today!
When you’re headed out to a job site, managing materials is critical. You want all of your materials to show up at the right time, in the right amounts. You need to inventory them; you need to store them properly. Sometimes, it may feel as though material management is half of your job! These five tips will make managing materials on the job site easier.
Managing materials on a job site is an ongoing process. Construction sites are often chaotic, filled with people moving everywhere and things that have to be done. Appropriately managing those materials will help give you a sense of confidence and make it easier for you to take care of your part of the job. Need help keeping moisture from creeping into your masonry materials? Contact us to learn more about the materials we can offer.
As all people that have an interest in masonry, it is important for us to realize that we often need help understanding new technologies, old traditions and why the architect drew such a thing. All information shared is only as good as the person communicating the concern. Now, I know I am not the world’s best communicator (ok, stop laughing), but when I am explaining a masonry situation that requires some assistance from a more experienced co-worker I need to be on my game. As an employee of one of the nation’s top masonry firms for many years, I had a variety of expertise at my fingertips, people who could jump in a truck and come to a jobsite without adding expense to my job.
That is what we all need, someone there who can help. Mortar Net Solutions™ has that service ready and waiting for you. Proud of their technical experience and innovation, Mortar Net can take a look at your jobsite condition and offer the suggestions you sometimes need to keep things moving. Oh – and it is part of our everyday service that we offer all of our customers.
Mortar Net Solutions provides an extensive and ever-expanding library of customer testimonials, and how-to and installation videos. The how-to and installation videos are shot with a focus on helping make the mason’s job easier. Based on the technical department’s most frequent requests from masons and designers, the videos have been developed to help educate and instruct the viewer using time proven techniques that are typically passed down from one’s mentor. Written and based on hundreds of jobsite visits where North America’s masons and project managers have discussed jobsite conditions, the videos are designed to solve specialty issues using universal techniques. Though products are referenced, the basis of the videos is the education that is presented as well as the techniques that are shared. Compatibility of products as well as the do’s and don’ts of mixing materials is broken down into simple talk.
As technology expands our trade with digital time clocks, automated estimating and accounting services, cellular phones and digital video cameras, it is great to know that the originator of the first mortar collection system allows its technical department the ability to share experience, and video equipment to assist the masons in solving problems with time proven techniques and quality products.
Showing the masonry industry Mortar Net’s commitment to the industry and the technical expertise that is part of our everyday service will provide the customer with confidence that their masonry-related questions will be answered correctly.
According to a recent survey from the Associated General Contractors of America, 83% of construction firms struggle to fill positions for qualified craftworkers. TotalFlash, LathNet and BlockFlash, MortarNet, CompleteFlash, and DriPlane are all products that provide superior performance while being quick to install. They are specifically designed to save labor time and costs, and to help contractors get more productivity out of the workers they have.
From the online news source, “Business Insider “: According to the NAHB, homebuilder sentiment rose more than expected in June and to the best level since January after holding steady during the four months in between. The National Association of Homebuilders’ housing market index for June climbed to 60 from 58, topping the forecast for a rise to 59.
To compile the index, the NAHB surveys its members for how they rate the current sale of new homes, as well as their outlook for sales and buyer traffic. Members across the country reported higher traffic and more committed buyers.
“Rising home sales, an improving economy and the fact that the HMI gauge measuring future sales expectations is running at an eight-month high are all positive factors indicating that the housing market should continue to move forward in the second half of 2016,” said Robert Dietz, NAHB chief economist. The components gauging current sales, sales expectations and buyer traffic all rose.”
Since many houses use adhered masonry veneers, this indicates a growing opportunity for LathNet sales, as well as an indicator that commercial construction will probably be good for the rest of this year too. While commercial and residential construction don’t move in lockstep, positive economic conditions such as a relatively low cost of money and the overall economic outlook influence both markets.
According to federal employment data released by the Associated General Contractors of America, construction employment increased in 244 out of 358 metropolitan areas in the USA and was unchanged in 44 areas. 70 areas saw a decline between March, 2015 and March, 2016. AGCA data shows that the building recovery continues to be broad-based geographically and by construction type. Declining areas are in the parts of the country that are most affected by declining energy prices. The data also indicates that skilled labor shortages will continue and will probably grow as demand for new building increases. An AGCA survey showed that 70% of firms are having a hard time finding qualified workers. Please spread the word to any young people you know that jobs in the construction industry are plentiful and that a college education isn’t necessary for most of them. Masons, for example, can be collecting a paycheck with as little as 2 years of training.
The International Masonry Institute (IMI) position on the value of designing sustainable masonry cavity walls as systems rather than as a grouping of individual components reinforces the value of designing and building with CavityComplete. CavityComplete is the first and only tested and warrantied total cavity wall system. www.cavitycomplete.com
CavityComplete includes Mortar Net Solutions products MortarNet, TotalFlash, CompleteFlash and WeepVent.
According to IMI: “Masonry systems provide maximum contribution when they are recognized as a system. The masonry system addresses moisture penetration, air infiltration, thermal performance and life-long resiliency. Therefore, in the case of a masonry solution, we are talking about much more than the installation of a finished material and are instead focused on the delivery of a high performing system that continues to provide payback to the owner in terms of energy and maintenance costs. Masonry systems are the most cost-effective options to arrive at energy-efficient and environmentally healthy buildings today.” http://imiweb.org/system-thinking/sustainability/
A lack of skilled workers in the masonry industry and construction in general continues to make it difficult or impossible for contractors to keep up with building demand. Ironically, according to this article from the Associated General Contractors of America, hiring has actually slowed recently. The question is, has hiring slowed because demand is falling off, is this just a temporary dip in hiring, or are there simply no more people available to hire? Read the article to learn more.
Mortar Net Solutions products help combat the labor shortage because they are designed to be installed quickly and easily, so they help reduce masonry contractors’ labor time, can frequently be installed by lower skilled workers, and let contractors get more done with fewer people.