Saponification of waterproofing material: Is there trouble just beneath the surface?
By Peter Craig
After 25 years involvement with exteriorwaterproofing in Florida, I am very aware of how dynamic this area of construction is. New products and techniques are constantly developed to meet market needs and niches. However, not all new products or methods have performed as anticipated. The result is that some waterproofing systems and installation methods have evolved through learning from our collective mistakes to what they are today.
When dealing with forensic investigation of older waterproofing applications, we have to bear this in mind when we evaluate the problems. The system may have been correctly installed per the recommendations and industry standards at the time, although the standards have since evolved.
One example is concrete repair over this period. The last 25 years has seen many new products introduced, seen repair methods evolve from “patches” to “repairs”, and the establishment of the International Concrete Repair Institute (ICRI) to help set and maintain industry standards.
Another is the waterproofing of plaza decks. About a decade ago, the acceptable “standard” within the waterproofing industry for plaza decks included using cold fluid-applied emulsion or polyurethane coatings, and did not include a drainage board or drainage mat. There was concern that a drainage layer would act as bond breaker.
If a drainage mat was specified it was often a budget cut victim.