Yes – we use food-grade, potable water-safe waterproof coatings specifically certified for use in water storage tanks. These coatings do not leach harmful chemicals into stored water and are different from the regular waterproof coatings used on roofs or walls, which are not safe for tanks holding drinking water.

Underground tanks face external water pressure from surrounding soil and groundwater, so waterproofing must seal against water trying to enter from outside as well as prevent stored water leaking out. Overhead tanks mainly need internal waterproofing to stop stored water leaking out through cracks, plus external protection against rain and UV exposure on rooftop tanks. The treatment approach and materials differ accordingly.

A professionally applied food-grade waterproof coating in a water tank typically lasts 5 to 8 years, depending on water quality, usage frequency, and whether the tank is cleaned and inspected periodically. Tanks exposed to harder water or frequent draining and refilling cycles may need recoating slightly sooner.

In most cases, the tank does need to be fully drained and dried before waterproofing treatment, since coatings need a clean, dry surface to bond properly. For tanks with localized active leaks, we can sometimes carry out injection grouting from the outside without draining, but for full waterproofing and re-coating, draining and surface preparation is necessary for a lasting result.

Cost depends on tank size, whether it is underground or overhead, the extent of crack damage, and the waterproofing system used. We provide a free on-site inspection and a written, itemised quote so you know the exact cost before any work begins.