by Stepan Altounian
Prospects of water damage to a building are not something that should be taken lightly. In the United States, water damage is the second most frequent reason for an insurance claim. In total, these claims account for a staggering $11 billion of insurance claims each year, and they are a cause of trouble for insurance companies and facility managers alike.
The conventional wisdom that should be applied to water damage is that it’s best to fix things before they actually happen. In California, for example, that would mean that all the buildings should be properly maintained and waterproofed before the rainfall from El Nino can cause damage to them. Regular maintenance plays an important role in making sure that all the structures are being protected from water, as do damage preventing practices. We will go over some of the essential points that need to be on every facility manager’s water damage prevention and maintenance list.
Finding Potential Trouble Spots
Some parts of a building should be more frequently and thoroughly inspected than others. Roofs should be regularly checked for leaks. Points where materials are spliced or joined should be given added attention. Drainage systems should be looked at regularly. Any outside horizontal structure that’s made from a concrete substrate, like a patio or a parking deck, should be inspected regularly. Vertical concrete surfaces, such as walls made from concrete blocks, are also due for an inspection. Inside the structure, any level below the grade is especially susceptible to water damage. Windows, throughout the whole building, are also potential spots where water can get in.
Vulnerable spots are the spots that are both exposed to water from the elements, and either have an innate flaw or are very prone to developing flaws. Take concrete, for example. It’s the most common material used to make outside structures such as parking lots, patios, and driveways. The innate flaw it has is its porosity – between 12 and 18 percent of the volume of concrete is in fact small holes through which water can get through. This makes parking lots, balconies, patios, driveways and any other structure made from concrete susceptible to cracking due to freeze and thaw cycles. This type of damage comes on top of all the other sources of potential damage to concrete. In parking decks, for example, the increased traffic of heavy vehicles can cause considerable damage, especially in combination with the degradation of the sub-layer due to water leaks. Balconies especially are susceptible to spall (i.e. break away) because the steel reinforcing bars commonly used in them rust over time and by doing so expand, which damages the concrete around them. For patios, the most common cause of damage apart from rain and snow is inappropriate draining which allows standing water to form. Concrete walls can crack due to settlement.
Knowing What to Look For
When you’ve identified the trouble spots, it’s time to look for potential causes of water damage. Improperly insulated joints can be a potential cause of water damage because they can leak water. All drainage systems need to be unobstructed or they will not perform their purpose and will allow standing surface water to gather. When it comes to concrete substrates, cracks and fissures are damages which can only get worse when water is added to them. For windows, the sealant applied when installing them wears out over time. When water starts getting through, the wear gets worse rapidly.
Waterproofing Trouble Spots
Some trouble spots, like gutters and other draining systems, only need to be cleaned regularly. Other trouble spots, like those made out of a concrete substrate, require a little more effort to be prepared for water.
Concrete can be sealed against water, and there are a couple of ways of doing it. There are special treatments which can be applied to concrete surfaces, penetrate the concrete, and then stop water from coming in. Various silicates are used for these purposes, for example. They are not applicable in every case because they don’t heal cracks in the concrete, so they should be used as an inexpensive and relatively short-lasting first line of defense for healthy surfaces. Silicone sealants can also be used to seal the joints between concrete blocks, and silicone caulking is also used to replace damage window caulking. If the concrete isn’t badly damaged or of substandard quality, concrete resurfacing can be used to give it a more appealing look, as can concrete overlays.
More substantial efforts on surfaces which are cracked or in bad shape should include methacrylate, polyurethanes, or elastomeric coatings. They can be used both as a coating for the healthy parts of the concrete slab, as well as a filler and healer for the cracks. Polyurethanes are a good choice, even though they are moisture-intolerant until they cure, so they have to be applied to a completely dry surface. Elastomeric coatings are the go-to solution for waterproofing walls, but they can be tricky to apply and usually require more than one coating for best results.
Special consideration should be given to waterproofing any below grade parts of the structure. Water pooling on the ground near the building walls might eventually cause water to leak into the below-grade levels of the building, so proper measures need to be taken to prevent this. First, the ground pitch should be adapted to move the water away from the building, especially if there are spots in below-grade rooms where water is constantly leaking. The foundation walls can also have their positive and negative sides waterproofed by applying special membranes which act as a physical barrier that prevents the water from getting into the walls, or getting from the walls into the rooms.
Maintaining Waterproof Status
After the preventive measures are taken and there’s little to no chance of water damage affecting the building, it’s important to follow all of the best practices that will help keep the building waterproof. Regular checkups of all the trouble spots should be a part of maintenance. However, it’s also important to note that some materials, like the silicates we mentioned earlier, have a limited lifespan and will eventually lose their effect. This is why it’s important to take note of all the measures taken to waterproof a building and their expected effective lifespan, and make sure that all of them are reapplied regularly so to prevent any future water damage.
Stepan Altounian is the manager of Sealwize of Southern California, specializing in commercial waterproofing, concrete repair, and polishing services.