Water tank waterproofing in Jazan: before summer & rain season

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

Before we start: what we know about Jazan

Jazan is about 1.9 km from the sea coast (OpenStreetMap). The centre of Jazan sits about 7 m above sea level (SRTM open elevation data).

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..

Water tanks in Jazan are most often let down by slow leaks at the joints between the tank walls and floor, and by cracks that open up as the concrete ages under heat. Once water works its way into these weak points it can seep into the surrounding structure, so the first sign many households notice is damp on the wall beside the tank or a stain on the ceiling below. Tank internal coating is typically priced at SAR 25–60 per m², and a sound job starts with the joints and any visible cracks rather than with the open surfaces, because that is where the water finds its way out.

Local conditions change how this work should be approached. The centre of Jazan sits about 7 m above sea level, and the city is about 1.9 km from the sea coast, so the air is humid and salt-laden for much of the year. That means the coating chosen for the inside of the tank has to tolerate constant moisture and mineral-rich water, and surface preparation matters more than usual, since salts left on the concrete can stop a coating from bonding. Crack injection, priced at SAR 40–120 per metre, is often the right first step before any surface coating goes on, so that the coating covers a sealed base rather than a surface still feeding water through hairline paths. Where the tank sits on or near a roof, liquid roof waterproofing at SAR 8–25 per m² or a bitumen membrane at SAR 15–35 per m² may also need attention in the same visit.

Before booking the visit, ask the provider to walk the tank with you and explain which joints and cracks they plan to treat and why. Ask them to state the coating system they intend to use and how they will prepare the concrete surface, and check whether they will drain and dry the tank before work begins. Request a written quote that lists each item by its unit rate, so you can see the cost of crack injection separately from the coating. Finally, ask how long the tank must stay empty after the work and what the provider will check before you refill it, because scheduling the job before summer or the rain season leaves the least room for delays.

Checks before summer and before the rain season catch problems while they are still small.

When do you need water tank waterproofing?

The following signs are worth checking before they grow:

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

Where the problem usually comes from

• Cracks in the walls or floor — we check this before anything else.
• A common cause: damaged old coating.
• Construction joints.

How we choose the tool in Jazan

From the first visit to the report

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.

Facts and costs — Jazan

Short answers for Jazan

Common mistakes we see

• Using a material that is not intended for drinking water

What you get after the work

You receive: the material name, its batch number and the fill-test result, in a technical report with a verification code.