Often in the design of a new underground construction in the presence of a water table, attention is focused on the product with the best performance in terms of technical, chemical and physical characteristics and therefore able to best protect the building during its service life.
There is therefore a tendency to evaluate the current section, leaving the management and choice of the best sealing method for aspects that are just as decisive for the watertightness of the entire basement, such as the penetrations (electrical cables, pipes, basins, drains, beams, etc).
It is true that the adoption of water-reactive systems can certainly facilitate the management and sealing even in after, but a correct waterproof design of the various discontinuities can certainly reduce the variables linked to site improvisation.
The preferred solutions
Without considering the pipes (pre- or post-cast), let’s try to consider how the simplest elements, such as spacers or formwork tensioning blades, can turn out to be, if not adequately guarded, elements through the waterproofing, preferential pathways therefore for the ingress of water.
The sealing of these elements should already be foreseen in the preliminary phase, adopting the appropriate devices and thus allowing the continuity of the waterproofing system to be obtained, an essential requirement when dealing with a basement area with the presence of water.
Penetrations through the waterproofing can be, as just mentioned, of a plant engineering nature (pipes), linked to construction methods (spacers) or also linked to structural aspects.
In certain areas of new construction it is not uncommon to face interferences such as pile heads, micro-piles, struts or tie-rods that punctually and recursively can represent a by-pass point.
Total protection
In existing areas subject to infiltration that are to be recovered and enhanced, or in reservoirs or swimming pools (skimmers, etc.), this issue may recur, which, addressed in good time and with specific and well-tested hydro-reactive methods, makes it possible to generate total protection of the buried area.
Example of sealing through body with hydro-expansive mastic
Example of sealing through body with epoxy adhesive and elastic tape
Can waterproofing be damaged?
Waterproofing can be damaged considering tough applications conditions and simultaneous presence of several different operators involving movement machines, rebars positioning, etc. In this way it is always recommended to choose a repairable active system in order to localize potential issues and properly repair the system anytime.
How do you waterproof a waste pipe?
Waterproofing a waste pipe is important to prevent leaks and water damage. Here are steps you can take to waterproof a waste pipe in order to limit potential diffusion of leakages in all structure:
- apply a preliminary drainage pipe to drive water outside the area
- clean the entire area with a radius of approximately 6cm
- apply an hydro-expanding mastic (or a hydro-swellaBLE waterstop) as gasket
- close the gap with quick-setting mortar
- apply a cementitious flexible coating as final waterproofing layer
