Floor & balcony waterproofing for warehouses in Jazan

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

Before we start: what we know about Jazan

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).

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..

Jazan sits close to the coast, and the centre of the city is only about 7 m above sea level, which means the ground is low and moisture can rise through slabs and collect around the lower edges of a warehouse floor. Because of this, the first things a technician checks on a warehouse floor or balcony here are signs of moisture coming up from below, such as darkened patches, salt bloom on the surface, or a damp smell near the lowest bay. The site is only about 1.9 km from the sea coast, so salt-laden air and groundwater deserve attention before any product is chosen. Cracks, joints and the drainage slope are also inspected early, since water that pools in a low corner will find its way into any weakness.

The points below are left to the site visit, because they depend on conditions that cannot be judged from a description. The technician will look at the actual condition of the existing surface, whether it is sound, dusty, oily or flaking, and whether old coatings need to be removed first. They will measure the length and width of cracks, decide whether crack injection is needed, and check how the balcony or floor drains and whether water is ponding. The exposed areas, the access routes for materials, and any ventilation limits inside an occupied warehouse are also assessed on site. Where a tank or a basement is included, its depth and its water exposure are confirmed in person rather than assumed.

For the technician, it helps to know the scope of the job in square metres and linear metres, since rates for this work are often quoted per square metre, with crack injection quoted per metre. The usual options include liquid roof waterproofing, bitumen membrane, epoxy coating, spray foam, and XPS boards, and each has its own range of cost, so the choice should follow the findings from the site. Note whether the floor carries heavy racking or traffic, whether the area is a balcony exposed to weather, and whether any internal tank coating is part of the request. Clear photos, sketches with dimensions, and a record of where water has been seen will allow a precise estimate and a sound repair plan.

For warehouses, work is phased around operations and stored goods.

Signs worth paying attention to

The following signs are worth checking before they grow:

• Water passing from the balcony to the floor below
• A wrong fall towards the door threshold
• Damp under the light well

The most common causes

• A threshold without waterproofing.
• A common cause: incorrect falls.
• A blocked drain — we check this before anything else.

Tools and methods, and when we use them

The steps in order

1. Checking the falls: Where water collects and where it should go.
2. Details: Thresholds, drains and upstands.
3. Waterproofing: The layer is applied and protected.
4. Flood test: Tested before the finish goes on.

Facts and costs — Jazan

Questions from Jazan

Common mistakes we see

• Tiling a balcony without waterproofing

The written outputs

The written output: the flood result and photos of the details. The report is numbered and can be checked with its verification code.