Damproofing or Waterproofing on walls?
There is a big difference between damp proofing and waterproofing. By definition, damp proofing is supposed to retard moisture but, unlike waterproofing, it does not have to stop hydrostatic water pressure. The old black stuff in a bucket is just hot liquid asphalt originally created for road repair. Nowadays, it is water-based. The thickness of the bituminous tar is not specified – it is only 10 mils thick at most when cured. It soon disintegrates due to the “alkali attack” from concrete – its life expectancy is between 18 months and 3 years. The tar damp proofing is inexpensive and meets the lowest minimum standard. Most building codes require that “unfinished” basement living spaces only be damproofed (no guidance on what to do if you later finish the basement). The codes usually also require that if masonry walls enclose a habitable space, they must be first covered with 3/8 inch thick parging made of Portland cement. Damp proofing may be acceptable if there is a sandy soil and gre
