Seeping or Damp Internal walls and slabs


If you have seeping or damp walls or slab the answer could be Negative Pressure waterproofing, a term you may encounter on occasion. Whilst not used as commonly as standard positive waterproofing, there may be times when will recommend negative waterproofing, either during new construction or for civil, commercial, strata or government remediation projects.

At we use negative waterproofing in very specific circumstances and most commonly in basement tanking and  damp slabs.

Our guide to negative waterproofing includes the differences between positive and negative waterproofing, and negative waterproofing techniques, benefits and best applications.  applies waterproofing membranes to flat concrete roofs, box gutters, under tile bathrooms, wet areas laundries, balconies as well as external  retaining walls. In these cases, where we install the membrane to the exterior face of a structure, it is termed ‘positive’ waterproofing.

Positive waterproofing is the standard type of waterproofing membranes and are most commercially available waterproofing systems suitable for these external applications.

As the name suggests, negative waterproofing is applied to the internal or ‘negative’ side of a structure.

Generally, we opt for negative pressure  waterproofing for a very practical reason, that is ease of access. There may, however, be other occasions where would recommend negative waterproofing as part of a comprehensive waterproofing strategy.

Negative pressure waterproofing may consist of a correction to the substrate for enhanced protection against water ingress and negative hydrostatic coating as a final protective layer in your waterproofing solution.

Positive waterproofing works by preventing water from entering a substrate and waterproofing membranes can offer additional features such as resistance to chemicals, UV or extreme weather. Negative waterproofing does not prevent water from entering a substrate, but it has a specific advantage.

On completion of a waterproofing project such as a concrete flat roofs, box gutters,   under tile bathrooms, laundries, wet areas, balconies, the remedial process after membrane installation includes tiling, concreting, decking, drainage or landscaping. This means the membrane is sealed within the structure and we can only access it with a second remediation project to remove and then rebuild the layers above the membrane.




Seeping or Damp Internal walls and slabs

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