Investigate Leaks

Words: Bronzella Cleveland

MCAA Magazine

Jerry Painter  

Subject: Investigate Leaks I received a unique call the other day from someone with a water intrusion problem. During a driving rain he had experienced water going straight through a split-faced CMU wall. So now they had my attention! Straight through, huh? Now, I’ve seen all kinds of lumber go through masonry walls as a result of wind tests as well as storms. I’ve seen where cars have gone through masonry walls. There was even a truck stop on I-10 that makes it appear a railroad car derailed and went through a block wall. But I’ve never seen water penetrate straight through a CMU wall unless there was some form of opening involved. The only way to truly determine a water intrusion through a wall is by performing a visual assessment, and possibly a water pressure test, on the wall in question. On occasion, a good look at the wall, and the “as built” drawings can sometimes uncover something very obvious that may have just been overlooked.   There are three important factors to water intrusion: (1). A point of entry, which is not always obvious. (2). The path of travel that the water follows – with gravity. (3). An exit point. In this particular case, the owner does not want to do any investigating. At this time they would just like to stop the water penetration of the affected area with a waterproof coating and are unwilling to investigate the under-lying cause of the problem. Naturally, as a super fan of Masonry - I do not agree with their decision. I have personally seen properly installed (colored) CMU’s that are still functioning wonderfully with no leakage. The proper tooling of mortar joints, and a good quality smooth faced CMU with properly installed weeps, will provide a very good weather-proofed wall. This particular structure is over 10 years old. It has colored split-face CMU. There are no records to determine if the masonry units contained any integral waterproofing. Although I think I could find that out in 3 or 4 phone calls. When CMU’s are split during manufacturing, it removes the smooth dense face and exposes the aggregate, which in turn increases the potential for water absorption of the unit. Producers have been including integral waterproofing in colored architectural units for many years. When these units are installed along with the mortar that has the same waterproofing material, it creates a very good water resistant wall. Getting back to the problem building at hand, the photos showed that there were attached canopies over the storefront and doors. It turns out that the leakage is adjacent the store front. I am not a gambling person, but I would bet you all the Gator Tail you can eat that there is definitely a breakdown in the flashing and sealants that will give water the opportunity to collect and penetrate the wall. It would then flow downward, and as we all know, gravity ALWAYS works!!! So without an investigation, the owner simply says “the masonry is leaking” and is asking about putting some type of sealer or coating on the CMU. The simple answer is yes. BUT, they should find a reputable, insured and bonded contractor to do that sealer or coating. Masonry deserves a better treatment than being accused - without any proof of any wrong doing. Masonry, when properly designed and installed is a very durable, functional, adaptable, and economical art form. If you have any questions about any codes and/or standards…send them to MCAA. We will do our very best to help you find the answers to any question. As always, don’t forget to: Raise the line and come on around the corner!!!  
About: Painter's Corner
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