Do you know the phrase, “What you don’t know can’t hurt you?” The reason it exists is a mystery to most because in fact what you don’t know can hurt you badly.
When buildings suffer water intrusion and the cause is unknown, the owners and tenants are definitely “hurt.” It’s difficult to run your business every time a storm or rains happen, it results in puddles inside your unit. Detecting and treating the unknown is often necessary to ensure normal business operations.
Waterproofing issues are often rated first among construction complaints, especially in surrounding coastal areas.
Experience has proven that 90 percent of water intrusion problems occur within 1 percent of the building’s exterior surface area. The problems can stem from a lack of quality control during installation, or various details may have been overlooked when the exterior waterproof systems were installed. All too often, when buildings are constructed, waterproofing systems are designed into a building and chosen independently. They perform independently that way, instead of in a cohesive manner.
To prevent water intrusion into any building, it must be enveloped, from rooftop to the below-grade foundation, with the correct waterproofing materials and systems. Whenever an individual system fails, or the groups of systems fail to perform together, leaks can occur. Roofing, below-grade and above-grade foundation, damp-proofing and flashing all cohesively must perform to create a barrier to protect and waterproof the building from top to bottom
Often, it is not the manufacturer’s waterproofing system that fails, but the field construction details of transitions and terminations when the buildings are constructed. An example of a transition is when a window meets a masonry or stucco surface. The building meeting the ground is an example of a termination. Not following the instructions for application from start to finish during the building’s construction is where the problem is created. Waterproofing systems not only prevent water from damaging your drywall and flooring, but they stop pollutants that cause costly repairs. Areas to watch for damage are concrete spalling* and structural steel deterioration, especially on exposed horizontal areas, such as balcony decks and parking garages.
Remedial waterproofing is needed when water has infiltrated existing buildings. For remedial work being performed on the exterior substrates, there is never one product that solves all the problems. These products can also be different than those used in new construction applications. A typical case is when a unit owner on the 3rdfloor of a 12-story building complains of water along his baseboard, wet carpet, and stains on drywall around his window. Right away, he suggests water is coming through the stucco wall and his window leaks, which of course can very well happen and does. However, when questioned concerning the condition of the roof, roof flashing, roof parapets or areas not associated with the location of the damage itself, the reply is often, “You mean if an area on the 12thfloor leaks I can have water in my unit on the 3rdfloor?” Most often people find that hard to believe and have never heard the statement, “water seeks its own level.” Water is not particular as to what floor it stops at.
When leaks do occur it’s always practical to have a qualified professional perform a comprehensive inspection. Some steps to remember:
1. Do an extensive inspection of leaks and damage.
2. Determine and locate the cause.
3. Choose the correct repair system.
4. Properly prepare the substrate.
5. Perform any restoration work.
6. Apply the waterproofing system.
Maintaining the exterior of your building, to keep it watertight may sometimes seem like a never-ending battle, but it doesn’t have to be that way. Stay on top of it and don’t put your trust in that old phrase, “What you don’t know can’t hurt you?”
*Note: Spalling is when the iron rebar in concrete has oxidized, causing the coating on the concrete to bubble. Spalling concrete is largely due to a natural deterioration process called carbonation. Carbon dioxide in the air diffuses into the concrete and reacts with the alkalis in it. The concrete becomes carbonated and this allows the embedded steel bars to corrode. These corroded steel bars expand and exert a force on the concrete to bulge and crack.