Bitumen membrane for duplexes in Jubail

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

What is specific about Jubail for bitumen membrane

The centre of Jubail sits about 4 m above sea level (SRTM open elevation data). Jubail is about 0.9 km from the sea coast (OpenStreetMap).

Team note on Jubail: 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..

Is a bitumen membrane the right choice for a duplex in Jubail, and what does it cost? Jubail's city centre sits about 4 m above sea level, and the coast is roughly 0.9 km away, so the area is close enough to the sea that moisture and salt-laden air are part of the picture for any roof or wall. Bitumen membrane for a duplex is typically priced at SAR 15–35 per m², which sits in the mid-range of the waterproofing options we offer. Compare that with liquid roof waterproofing at SAR 8–25 per m² and spray foam at SAR 20–45 per m², and you can see where a membrane fits within a broader budget. The right choice depends on the surface, its condition, and how it will be used.

Before any work is quoted, the inspection walks through the duplex roof and any surfaces that will be treated. The technician looks at the existing membrane or substrate, notes any blistering, lifting edges, or ponding areas, and checks the upstands, drains, and joints where water is most likely to get in. Where cracks are present, crack injection at SAR 40–120 per metre may be discussed as a separate line item, so the inspector measures any run of cracking in metres. The inspection report then sets out which areas are recommended for bitumen membrane and which may need a different approach, such as XPS boards at SAR 12–30 per m² for insulation under a protective layer.

To make the visit efficient, have the roof access ready and clear loose debris from the surface before the technician arrives. Note any past leaks, the date of the last repair, and any areas inside the duplex where stains have appeared on ceilings or walls. If the building has a basement or bathrooms that you want included, mention them at booking so they can be measured separately, since basement waterproofing (SAR 50–150 per m²) and bathroom waterproofing (SAR 15–40 per m²) are priced on their own terms. Having this information ready lets the inspection focus on the work that matters and produces a clearer quote.

In a duplex, the two floors often share lines, so tests are done floor by floor.

When do you need bitumen membrane?

These are the signs most often linked to bitumen membrane:

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

Causes we see in the field

• No protection layer — we check this before anything else.
• A common cause: seams that were not welded properly.

How we choose the tool in Jubail

From the first visit to the report

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 Jubail

Questions from Jubail

Common mistakes we see

• Leaving the membrane exposed without protection

What you receive

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