Waterproofing with prefabricated surface coatings

Building and civil engineering structures need to be protected from water, not only because the inside of buildings needs to stay dry, but also because water can damage them in a number of ways: it can corrode structural steel, cause thermal insulation (foam, glass wool) to lose its power, deteriorate materials through frost, and cause mold.

In addition, tanks, casings and basins must be watertight with respect to the liquids they contain (usually water, whether potable or not).

This means waterproofing roofs, walls or façades and building foundations, bridge decks, tunnels or underground structures, reservoirs and tanks.

There are several techniques to achieve this:

• materials can be waterproofed by coating them with waterproofing products (silicones, for example) or by incorporating mass water repellents;

• building structures can be sealed in several ways:

  • or by covering them with factory-prefabricated sheet or screed,

  • or by applying a coating such as plaster, paint or resin, applied in a liquid state, which then dries and hardens.

In this article, we'll focus on the second technique (sheet and screed coatings). It will focus on terminology, waterproofing rules, the different types of waterproofing products and coatings, and their characteristics.

A second article will look in detail at the various applications of waterproofing sheets, on roofs, flat roofs, foundations and engineering structures. Waterproofing of tanks, reservoirs, basins, tunnels and buried structures will not be covered, nor will that of façades.

Readers interested in other techniques for protecting building and civil engineering structures can consult the various sections of the Construction treatise.