Water tank waterproofing for residential buildings in Jazan

Prepared by the technical team · editorial review · last updated 13 November 2026 · Sources

Before we start: what we know about Jazan

Team note on Jazan: Kashf teams serve this city and its nearby districts with the same documented inspection standard: device-based leak detection without demolition, a written report, and a clear scope before any work begins.. The centre of Jazan sits about 7 m above sea level (SRTM open elevation data).

Jazan is about 1.9 km from the sea coast (OpenStreetMap).

Water tanks on residential roofs and at ground level in Jazan are often the first place where leaks go unnoticed, because the tank sits out of sight and damp patches appear only after the water has already been seeping into walls and ceilings below. The most common problem we see is seepage through hairline cracks and failed old coatings on the inner walls and base of concrete tanks, which lets water escape slowly and weakens the structure over time. Tank internal coating is priced at SAR 25–60 per m², and an inspection usually shows whether the tank needs a full recoating or only crack injection, which is charged at SAR 40–120 per metre.

Local conditions shape the approach. The centre of Jazan sits about 7 m above sea level, and the city is about 1.9 km from the sea coast, so tanks and the buildings they serve are close enough to the coast for salt-laden air and humidity to speed up deterioration of exposed surfaces and coatings. That is why the job should not stop at the tank itself. Liquid roof waterproofing, priced at SAR 8–25 per m², and bitumen membrane at SAR 15–35 per m² are often considered where the tank sits on a roof, since the tank and the roof beneath it share the same exposure. Where a tank rests on a slab, the surrounding floor and any bathroom above it may need checking too, so a single leak does not turn into damage across several areas.

Before the visit, ask the provider a few direct questions. Ask whether they will inspect the tank for cracks, joints and old coating failure, and whether they will check the roof or slab underneath, not just the water store. Ask which materials they propose and what each costs per square metre or per metre of crack, so you can compare the quote against the ranges above. Ask whether the water must be drained during the work and how the tank will be refilled and tested afterwards. A clear answer to these points tells you whether the visit will solve the leak or only cover the symptom.

For a residential building, shared risers, tanks and pumps are checked as one system.

Signs worth paying attention to

If you notice one of these signs in Jazan, it is a good moment to talk to the team:

• Unusual colour or taste in the water
• A tank that leaks after testing
• Deposits and flaking inside the tank

Where the problem usually comes from

• Construction joints.
• Damaged old coating — we check this before anything else.
• Cracks in the walls or floor — we check this before anything else.

Tools we use in Jazan

The steps in order

1. Emptying and ventilation: The tank is emptied and ventilated before entry.
2. Cleaning and preparation: Loose material is removed down to a sound surface.
3. Crack treatment: Active cracks are treated first.
4. Coating layers: A material intended for drinking-water tanks is applied.
5. Disinfection and fill test: The tank is disinfected and the level is monitored after filling.

Quick comparison: facts and costs in Jazan

Questions from Jazan

Common mistakes we see

• Using a material that is not intended for drinking water

What you receive

The written output: the material name, its batch number and the fill-test result. The report is numbered and can be checked with its verification code.