Water tank waterproofing for residential buildings in Zhra Lbn, Riyadh

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

Before we start: what we know about Zhra Lbn

The centre of Zhra Lbn is at 24.6329, 46.5531, about 15.3 km from the centre of Riyadh, with an approximate radius of 8 km. The service-area circle on the map below is drawn from this point. Main roads in or near Zhra Lbn: Western Ring Road, Najd Road, Taif.

The nearest wadi channel is about 1.8 km from the centre of Zhra Lbn (OpenStreetMap). The centre of Zhra Lbn sits about 747 m above sea level (SRTM open elevation data).

Water tanks on residential roofs in Zhra Lbn face a familiar problem: the tank walls and base crack or flake over time, and water seeps into the structure below or contaminates the stored supply. For this property type, the most common failure point is the tank's internal lining, which loses adhesion after years of wetting and drying in the Riyadh climate. Leaks usually show first as damp patches on the ceiling of the top floor, staining on the outer wall, or a drop in pressure as water escapes. Tank internal coating is typically priced at SAR 25–65 per m², and the surface area is usually modest, so the job is often completed in a single visit once the old material is removed.

Local conditions shape the approach. The centre of Zhra Lbn sits about 747 m above sea level, and the nearest wadi channel is about 1.8 km from the centre, so rainwater can run hard across rooftops during short, intense storms and pool around tank bases. Good drainage around the tank and a properly sealed roof area matter as much as the lining itself. Where roof surfaces are exposed, liquid roof waterproofing at SAR 10–25 per m² or a bitumen membrane at SAR 15–35 per m² can protect the surrounding slab, while spray foam at SAR 20–45 per m² suits irregular shapes. Cracks in the tank or the slab beneath should be treated with crack injection at SAR 40–125 per metre before any coating goes on, because coatings bridge only small movement.

Before booking a visit, ask the provider a few direct questions. Confirm which coating system they propose for the tank interior and whether it is rated for potable water, since the tank supplies drinking water in most homes. Ask how they will remove the old lining and check for cracks, and whether the price covers both the tank and the roof area beside it. Request a written breakdown by square metre and by linear metre for crack work, and ask what preparation the surface needs before the work starts. Finally, ask how long the tank must stay empty during curing, so you can plan water use for your household.

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

Signs worth paying attention to

These are the signs most often linked to water tank waterproofing:

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

Causes we see in the field

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

Tools and methods, and when we use them

How the work is done, step by step

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 Zhra Lbn

Short answers for Zhra Lbn

Common mistakes we see

• Using a material that is not intended for drinking water

The written outputs

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