Cementitious Tanking

Cementitious tanking is a traditional barrier type means of waterproofing a basement.  It works by creating a waterproof tanking slurry to hold back the water, and is often found in older property types.  We would not recommend it to be used solely for new build basement waterproofing, as thermal, vibration and settlement cracks can cause seepage of water into the basement. The system is also susceptible to build up of water pressure; the pressure can eventually build up and cause cracks in the masonry, allowing seepage and damp into your basement or cellar.

However, cementitious tanking may be of use in some circumstances.  It may be beneficial to use it when external ground levels are higher than the existing DPC, causing damp to cross the wall, into the building, as an alternative to reducing external ground levels, or installing a full basement waterproofing system.  For example, in historical buildings, decorative plaster work would have to be removed / covered up if using a cavity drain basement waterproofing system.  Cementitious tanking would only require the existing plaster to be removed up to external ground level, thereby reducing the amount of works to be carried out, and maximising retention of existing fabric and details.