Bitumen membrane in Jazan: before summer & rain season

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

Why bitumen membrane differs in 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..

Bitumen membrane on flat roofs is the most common waterproofing problem in Jazan homes and low-rise buildings. Roofs take the full force of the midday sun, and over time the surface softens, blisters and cracks, letting water seep into the slab below. Many owners only notice the problem when a ceiling stains after the first heavy rain, by which point the damage has spread along the edges and around drains and parapets.

Jazan's location shapes how that membrane should be planned. The centre of the city sits only about 7 m above sea level, and the coast is roughly 1.9 km away, so the air is humid and salty and surfaces stay warm well after sunset. Rain tends to pool on flat roofs when drainage outlets are slow to clear, so falls should be checked and outlets kept open before any new membrane is laid. Because moisture and salt can work into the base, the surface should be dry and sound before the bitumen goes on, and the detailing at upstands and penetrations deserves as much attention as the main field. Bitumen membrane usually falls in the SAR 15–35 per m² range, and a sensible plan balances that cost against how much of the roof is actually failing.

Before the visit, ask the provider to walk the roof with you and point out ponding areas, cracks, blisters and any previous repairs. Ask how they will prepare the substrate, how they will treat edges, drains and roof penetrations, and whether the price covers the surface works or only the membrane itself. Ask which sections they recommend for other options, such as liquid roof waterproofing at SAR 8–25 per m² or XPS insulation boards at SAR 12–30 per m², and why. Finally, ask them to schedule the work for a period when the roof can stay dry for the time needed to cure, and to confirm in writing what will be cleaned up once the job is finished.

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

When do you need bitumen membrane?

The following signs are worth checking before they grow:

• Old rolls that are cracking
• A flat concrete roof that needs waterproofing

Causes we see in the field

• Seams that were not welded properly.
• A common cause: no protection layer.

Tools and methods, and when we use them

How the work is done, step by step

1. Preparation: Cleaning, priming and repairs.
2. Torch welding: Overlaps are welded and checked.
3. Details: Upstands, drains and bases.
4. Protection and flood test: Protection is laid after a successful flood test.

Quick comparison: facts and costs in Jazan

Questions from Jazan

What we advise against

• Leaving the membrane exposed without protection

The written outputs

You receive: photos of the welds and the flood-test result, in a technical report with a verification code.