Expertise
Waterproofing & tanking
Water does not stop for good intentions. It finds the weak point — and the weak point is always a detail of execution: a construction joint, a service penetration, a seal.
Two strategies, not to be confused
Positive side — treating from the water side. Physically, this is the correct answer: the membrane is pressed against the substrate by the water pressure itself. It is applied in new construction, before backfilling. It is the cheapest and the most durable. It has one permanent drawback: it becomes inaccessible.
Negative side — treating from inside, against the pressure. The membrane works in tension against debonding: any weakness in adhesion, and the water lifts it. It is the only route available on an existing structure, and it demands materials that become part of the concrete — crystalline mortars, capillary-penetrating systems — rather than a film laid on the surface.
Tanking is a different discipline again: it is not about keeping water out of a room, but about keeping a liquid inside a structure — or guaranteeing that it stays potable. A drinking water tank requires products certified for food contact; a wastewater plant requires resistance to H₂S, which turns into sulphuric acid on the walls and devours concrete within a few years.
Method
What we actually address
Hydraulic diagnosis
Where is the water coming from? Permanent water table, surface run-off, capillary rise, condensation? The treatment differs. Seasonal infiltration and a pressurised water table do not call for the same solution.
The details
Construction joints, service penetrations, day joints, re-entrant corners. That is where water passes, almost always. Waterstops, hydrophilic seals, resin injection — each case has its own answer.
Stopping active leaks
Before any waterproofing, active water ingress must be cut off: ultra-rapid setting mortars, pressure injection of expanding polyurethane resin. You never lay a coating over a leak.
The waterproofing system
Bituminous or synthetic membranes on the positive side. On the negative side: waterproofing mortars, crystalline systems that seal the concrete's porosity from within, epoxy or polyurea coatings depending on the liquid contained.
Protecting the substrate
In a wastewater plant, waterproofing alone is not enough: the concrete must be protected from H₂S. In a drinking water tank, migration must be prevented. The contents dictate the coating.
When to call us
The structures we treat
- Basements and underground car parks — infiltration, water table
- Foundations and rafts in new construction
- Potable water tanks and reservoirs
- Wastewater treatment plants and aeration basins
- Retention basins and containment areas
- Service pits, lift shafts, buried plant rooms
- Dams and hydraulic structures
- Flat roofs and accessible terraces
Track record
Structures we have made watertight
Projects delivered by Jawad Izallalen under the PROJET-TS name, or in the course of his successive roles at SPTS, BASF and ADROC.
- Potable water tanks for ONEP, LYDEC, REDAL, AMENDIS
- Tanking of the reservoirs at the Coca-Cola NABC plant, Marrakech
- Waterproofing of foundations and car parks, IDUNE complex, Casablanca
- Casa Ocean wastewater treatment plant
- Timkit and Ouljat Essoltane dams
- Lining of 3 km of phosphogypsum discharge pipeline
Frequently asked
What we are asked most often
My basement is already built and it leaks. Does everything have to be excavated?
Not necessarily. Excavation is the ideal solution but rarely realistic on a structure in service. A well-designed negative-side treatment — sealing active leaks, detailing the joints, crystalline mortar — gives excellent results. It simply demands more rigour.
Are waterproofing products compatible with drinking water?
Only those holding a certificate of sanitary conformity. This is a regulatory matter, not a commercial one. We specify only systems approved for that use, and we provide you with the certificates.
Why does a wastewater plant destroy concrete so quickly?
H₂S released by the effluent is oxidised by bacteria on the walls, above the water line, and turns into sulphuric acid. Local pH can fall below 2. The concrete is not attacked by the water — it is attacked by the air above it. The zone that appears dry is the one that must be protected.
Is resin injection durable?
For cutting off an active leak, yes — expanding polyurethane resins are highly effective and durable. But injection does not replace waterproofing: it blocks a water path. If the concrete is generally permeable, the surface must be treated.
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