(One Hundred Questions on Waterproofing) In underground basements of #95domestic buildings, there is often a phenomenon of inexhaustible seepage and continuous water leakage. Is there an advanced waterproof material or construction method that can achieve a permanent waterproof function?

Answer:

(i) Waterproofing of continuous walls has a significant difference in basic design and construction concepts: in foreign countries, defining continuous walls as a hypothetical project for retaining walls inherently constitutes inferior quality concrete, and cannot be considered a main structure (in Japan, after continuous wall waterproofing is completed, a 30-50 cm thick RC wall must be constructed as a main structure); while in China, continuous wall support is directly used as a main structural structure, with only a drip-proof and waterproof plaster applied, and all leakage issues are passed on to the waterproofing contractor; it should be noted that although part of the reason for the success or failure of basement waterproofing projects depends on the quality of the waterproofing materials and the proficiency of the construction techniques, the majority of the reasons are determined by the high or low level of groundwater and the strength of the structure itself. As a result of the vicious market competition and the tendency to bid for low prices, when waterproof contractors undertake sloppy construction work, they discover that the situation is not satisfactory; they are more likely to abandon the final payment rather than take the responsibility to properly repair the problem; it is no wonder that the more they try to make up for the losses, the more the leakage continues; the victims are the builders and consumers.

(ii) Therefore, as a second option, faced with the current domestic construction culture, we recommend that continuous wall waterproofing be implemented using the following leakage-proof waterproofing techniques, combined with the basic concept of guiding water flow during construction:

1. First, the finished parts are drilled, cut, and sealed; the areas with excessive water flow on the wall are also sealed to prevent the infiltration of carbonated salt crystals during the waterproofing process (commonly known as the “white birch phenomenon”), thereby clogging the drainage holes.
2. The bottom of the double-wall intercepting ditch must be properly reinforced to prevent water from entering—to prevent intercepting water.
   The accumulated water from the ditch seeps out.