What is the best concrete block wall sealer? Concrete blocks and concrete cinderblocks were once extremely popular as the foundation for basements. But with the extremely porous nature of cinderblocks and concrete blocks, water, moisture and efflorescence problems are extremely common.

Today poured foundations with reinforced steel footings have taken over as the basement foundation of choice. However, if your basement is comprised of these concrete blocks there is a solution to seal them and prevent all of these problems from precipitating.

Concrete blocks and cinderblocks are especially susceptible to moisture and water seepage and because of their porosity water easily finds it way underneath the surface, sitting in the numerous air pockets to fester and eventually spawn mold, mildew, and other issues. Because of the porous nature of these blocks, small holes and air bubbles force moisture and water through the voids if the block is not properly sealed. Not only that, water can also find its way through the mortar with a lot of water seepage occurring from these areas.

Using a silane/siloxane blended sealer like Siloxa-Tek 8500 with its blend of large and small molecular particles, will penetrate the surface and chemically react to form a water repellent barrier. As the barrier is below the surface it will not crack, peel, fade or yellow over time. At least two applications, wet-on-wet are required; by applying two coats versus one heavy application the material is able to penetrate deeper and more evenly.

8500 Concrete Sealer Bottle

Siloxa-Tek 8500

Water & Salt Repel

Published Monday 15th of July 2024 // Updated Tuesday 9th of March 2021

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