Dictionary of Moisture Protection & Restoration

Barrier Systems (continued)

Water repellents should not be considered as a typical barrier for waterproofing purposes. They penetrate the substrates, filling the pores. After curing, they remain as a solid material or shield that provides water repellency. They are identified as: acrylics, silanes, siloxanes or stereates, depending on their composition. Which water repellent to use is a complex process, which cannot be covered in this handbook. I suggest that you refer to the SWRI “Clear Water Repellents for Above Grade Masonry and Horizontal Concrete Treatments Manual”. This publication will give you a complete understanding of water repellents and a clear comparison of products.

Here is an example of and option of water repellent use. In my backyard, this Cherub was cleaned every spring and would turn green with mold every winter. In the summer of 2000, I cleaned it and applied a siloxane clear water

repellent to the left side, leaving the right side untreated. In April 2002 the difference was obvious. Water repellents do not provide the unper- meability requirement to be considered an acceptable barrier.

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