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Applying a Concrete Sealer

By September 19, 2012How To

There are many things you should keeping mind when applying a concrete sealer. Generally these can be categorized into surface preparation, sealer application and inspection. This way it is easier to follow along because you will know what phase you ought to be in regarding any specific topic. The assumption is made that you already have your materials in hand and are ready to go.

Following that line of thought, the first thing you need to consider before applying a concrete pond sealer is how the surface ought to be prepared. Concrete, like many other surfaces has its own unique properties that need to be examined before applying anything to it. First and foremost is the type of concrete that is being sealed. There is some confusion at times in regards to what concrete is. Concrete is a mixture of sand, rock, cement, lime and water. The sand and rock components can actually vary in size some which will eventually determine the over-all strength of the concrete in the end.

Mortar is not concrete nor is cement concrete although these terms are by and large used synonymously to describe concrete. The fact is that mortar for example, is use mainly for adjoining brick or block but should not be used where concrete should be. Mortar has no rock and if used like concrete, will end up being too weak to perform properly.

With that said, it will now be assumed that you are working with concrete. The surface preparation for new concrete dictates that the concrete cure at least 28 days before preparing (7 days for accelerated concrete). Once cured properly, the concrete is cleaned using a mixture of one part muriatic acid and three parts water to clean the calcium sulphate from the surface. It is rinsed off and left to dry. Older concrete should be cleaned the same way.

Now you are ready to begin applying a concrete pond sealer. There are four types of tools that can be used to accomplish this:

Tool Pros Cons
Paint Brush Good for tight areas and cutting in Difficult to control sealer thickness
Paint Roller Excellent for moving material over
larger areas
Sealer applied thinner so multiple coats may be necessary to build up to the minimum thickness
Squeegee Great for smooth surfaces, coating can be applied in one coat Poor for uneven surfaces, can be tough to learn for new users
Spray Gun Perfect for larger areas both smooth and uneven especially when larger amounts of material need to be applied Not ideal for small jobs

While each of these methods is equally as effective if done properly, it is important that all instructions are followed.  In the case of Pond Shield epoxy, there are very specific recipes for mixing the sealer that should be used.

With that said it is best to take you time and really make sure that you have covered the surface well. After applying the concrete sealer, you need to inspect the surface. Most people tend to think that if the sealer looks good from afar that it must be completely intact. This is not true. The concrete surface may have small flaw that will allow a sealer to settle down into leaving very small areas that are not entirely coated anymore.

Because of this it is recommended that each square foot of surface be inspected for flaws and touched up as necessary. All it takes is one flaw to become a leak that will more than likely cause you more grief than it could have if the small amount of time was spent inspecting the surface before the sealer was put into service.