We’re going to go over the top five tips for a successful waterproofing installation application. When a tile cracks or comes loose, it’s usually a pretty simple fix. But when it comes to waterproofing, waterproofing to be a costly failure. When we think of how water penetrates into all the adjoining areas – the walls and ceilings – and destroys all the other finishes, it can really be a mess. So today, we’re going to go over these tips in order to help you to avoid these costly failures.
1. Preparation is the key
Assure that the surface is clean, sound and dry before you apply the membrane. Assure that it’s porous, so it will accept the bond before you begin. If you see any gaps, for example in the corners of the seams, all of these may have to be treated with a sealant or backer rod some type of mortar with an alkali-resistant tape. Assure that your surfaces dry before you begin. Although most waterproofing membranes also serve as crack isolation membranes and are very flexible, they still have to be well supported. This is particularly important for your plumbing assemblies; they also need to be well supported in order not to deflect and cause damage to the membrane. Movement joints should be treated accordingly. The Tile Council detail CEJ171 defines how each type of joint should be treated. When you have a movement joint or you have a crack that’s out-of-place, you’re going to have to pay particular detail in order to treat that joint properly so the movement won’t affect your membrane.
2. Check pitches for proper water evacuation
Make sure that your substrate has the proper pitch before you apply the membrane. If you need a patch or a mortar bed in order to accomplish this, you can do so. The proper pitch, according to industry recommendations, is a quarter-inch per foot away from the building or to the drain. Your pitch must carry through to the tile surface in order to be effective. If not, you’re going to have depressions and birdbaths. What these will do is collect or pool water, and they can lead to serious freeze-thaw failures or extreme cases of efflorescence. In an interior environment, you might see cases of mold, because now you’re creating a condition to pool water and all the other things necessary for mold.
3. Apply your membrane at the correct thickness
Why is this important? Well, membranes are tested at a certain middle thickness, and they have to deform – they have to withstand a certain amount of pressure. In order to do that, they have to be applied also on your project at the correct thickness. That thickness is thirty miles. You can check the thickness of your membrane while you’re installing it by using something like a wet film gauge. It’s a little easier than trying to measure the thickness after you’ve applied it. After you’ve applied your membrane, it should be about a thickness of a credit card. Whatever method you choose to apply the membrane, assure that you get a smooth, continuous film. The last thing you want is any pinholes in your membrane. If you do see a pinhole in the first coat of membrane, make sure that in your second coat, you fill that hole and that you apply over it order to get the correct thickness.
4. Allow your membrane to dry sufficiently
One of the most common mistakes we see in waterproofing is applying one coat of waterproofing, and then not waiting long enough before you apply your second coat. It’s critical to allow these membranes to dry at their sufficient rates. When we test the waterproofing, or when you read on a package that a waterproofing takes a certain amount of time to dry, remember these are laboratory conditions. So at seventy degrees with fifty percent relative humidity, you can expect that your waterproofing will dry in a certain timeframe. When you have cold or damp conditions, for example over a mortar bed or new concrete where there is some moisture, you’re going to have to allow an extended period of time for it to dry.
5. Always choose the right mortar when installing over a waterproof membrane
Currently, what are our recommendations? Well, our recommendations are based on the Tile Council handbook, which tells us that a 118. 4 mortar approved by ANSIis required for use over an A118. 10liquid-applied membrane. Why do we need one? A polymer-modified or latex-fortified mortar will help you achieve a chemical bond and higher performance when installing over a membrane. These membranes, remember, repel water, so having a strong chemical bond is important. It’s important to have a high-performing mortar with a strong chemical bond in order to allow your tile to stay well-adhered while the membrane is expanding and contracting, as well as performing in your tile installation. If you follow this, you’ll have a very strong success rate in bonding over membranes.