Water Tank Waterproofing

Sika treats a water-retaining structure as a four-part system rather than a single coating: external waterproofing to keep groundwater out of a below-ground tank, watertight concrete with waterstops at the joints, internal waterproofing and protection on the surface in contact with the stored water, and concrete repair where there is localised damage. Which parts you need depends on whether the tank is above or below ground and on its condition. Sika's own guidance is that the selection of the best system depends on many factors including local water conditions, the nature of the reservoir structure and the water quality.

On its potable water treatment plants page, Sika lists waterproofing mortars (SikaTop-107 Seal, Sikalastic-1K, Sika-110 HD), multi-layer epoxy resins (Sikagard-62, SikaCor-146 DW), hot-spray polyurea membranes (Sikalastic-840 ES, Sikalastic-836 DW) and TPO sheet membranes (Sikaplan WT 4220, WT 4300) for internal waterproofing and protection. For joints it lists Sika Waterbar, SikaSwell A and Sikadur-Combiflex SG; for repair, Sika MonoTop-1010, Sika MonoTop-4012, Sika Injection-201 CE and Sika Injection-306. Of these we stock SikaTop-107 Seal AE, SikaSwell A, Sikadur Combiflex SG, Sika MonoTop-4012 and Sika Injection-201 CE. Tell us the tank holds drinking water when you enquire and we will confirm the approval position for your specific application before quoting.

Yes. Sika lists two membrane routes for potable water structures. Hot-spray membranes are two-part, elastic, 100% solids polyurea systems (Sikalastic-840 ES and Sikalastic-836 DW). Sheet membranes are flexible TPO systems (Sikaplan WT 4220 and WT 4300), thermally welded. For below-ground tanks Sika also lists external fully-bonded polymeric sheet membranes, SikaProof A+ and SikaProof-808, applied to keep groundwater out of the structure. Alongside those, waterproofing mortars such as SikaTop-107 Seal are used as a rigid internal system. Which route suits depends on the structure and the water quality, so send us the details and we will come back with the system.

Sika's guidance is that when there is loss of water in reservoirs or tanks due to localised damage in the rigid waterproofing system, the repair must be compatible with the existing waterproofing system, whether that is watertight concrete or a structure lined with waterproofing mortar layers. The repair route depends on the damage: concrete spalling is addressed with repair mortars such as Sika MonoTop-4012, cracks and voids by repair injection with resins such as Sika Injection-201 CE, and joints with Sikadur-Combiflex SG tapes. Send us photographs and the tank details and we will identify the compatible system.

Sika identifies eleven common exposures affecting water storage areas: low pH value, soft water, fungi, hydrostatic pressure, algae, micro-organisms, disinfectant, stray currents, water turbulence, chlorine, and the alkalinity of the concrete itself. Understanding which of these applies to your structure is what determines the right system, because a coating that handles chlorine and disinfectant is not necessarily the one that handles hydrostatic pressure from outside. Sika's design considerations are durability and water-tightness, exposures and site conditions, maintainability, food safety, compatibility of systems, and life cycle costing.

Yes. We hold stock in Riyadh and Jeddah and deliver to project sites across the Kingdom, including Makkah, Madinah, Dammam, Khobar, Jubail, Yanbu, Taif, Abha, Tabuk, Qassim, Hail, Najran and Jazan. Tell us the tank size, whether it holds drinking water, and the date you need the material, and we will confirm quantities and the delivery window with your quotation.