Page 349 - Construction Waterproofing Handbook

REMEDIAL WATERPROOFING 8.9

FIGURE 8.7 Steam/pressure cleaning of substrate. (Courtesy of Devcon)

Building cleaning is therefore a necessary part of building preservation and proper mainte-
nance. Cleaning should not be put off until remedial and restoration applications are necessary.
Exterior cleaning is completed by one or a combination of these methods:
● Water cleaning
● Abrasive cleaning
● Chemical cleaning
● Poultice cleaning
Before cleaning by any of these methods, testing of the proposed method is impera-
tive. Testing ensures that cleaning systems are adequate for the degree necessary and that
damage to the existing substrate’s adjacent materials and existing waterproofing systems
will not occur. Sample-testing a lower building portion in areas away from high traffic
and visibility is desirable.
Cleaning is normally completed before starting remedial repairs. In some situations, how-
ever, a building can be in such a deteriorated state that introduction of chemicals or water
under pressure will further damage interior areas and structural components. In these situa-
tions, sufficient remedial repairs may be required before cleaning, to prevent further damage.

Water cleaning
Building cleaning done later includes pressure washing, water soaking, and steam clean-
ing (Fig. 8.7). Pressure washing is the most common procedure, especially when it is