Sanitary Drainage & Sewerage Piping
NLS Contractors installs sanitary drainage and sewerage piping in Riyadh, Jeddah, Dammam and Khobar and across the Kingdom: soil, waste and vent stacks in uPVC or HDPE, floor drains, cleanouts, manholes and the connection to the public sewer. Work follows SBC 701 and National Water Company requirements, with test records, invert levels and as-builts at handover.
Drainage works by gravity, so the drawings that matter most are the levels. A stack, a branch and a manhole are each set to a fall, and one pipe laid flat can back up a whole block. The scope covers soil, waste and vent stacks, branches to each fixture, floor drains, cleanouts, manholes and the line to the connection point.
Stacks and branches are uPVC or HDPE, as the specification names. Floor drains hold a water seal that keeps sewer gas out, and drains that are rarely used need that seal topped up or primed. Vent pipes let air in behind the flow and out through the roof. Cleanouts go at changes of direction and at the base of stacks, where a blockage needs rodding. Where pipes pass through slabs and fire-rated walls, sleeves and sealing follow the specification.
Pipe size follows the load each stack and branch carries, which the design calculates from the fixtures served. Swapping in a smaller pipe or a different material to save cost changes capacity and the fall needed, so any change goes back to the consultant before it is built.
Below ground, the lines run from the building to the first manhole and on to the public sewer. Bedding, falls and invert levels are surveyed and recorded. Where the project joins the public network, the connection follows National Water Company requirements, and the invert levels at the connection point are agreed before the line is laid.
Air or water tests prove stacks and below-ground lines before they are covered. The record names the section, the test method and the result. Trenching and large external sewer networks sit under a separate underground utilities package, and the building drainage here stops at the agreed boundary.
Price depends on pipe material and diameters, stack and branch count, manhole depth and the length of external line. Lead time depends on scope and the offer states it. Send the drainage layouts, riser diagrams, the invert level schedule, the specification, the BOQ and the site city.
Specifications
- ✓Pipework: soil, waste and vent stacks in uPVC or HDPE
- ✓Components: floor drains, cleanouts, manholes, traps, vents
- ✓Gravity falls and invert levels surveyed and recorded
- ✓Standards: SBC 701, project specification, National Water Company (NWC) connection requirements
- ✓Tests: air or water test of stacks and below-ground lines
- ✓Handover: drainage layouts, invert level schedule, test records, as-builts
Frequently Asked Questions
What is an invert level and why does it matter?+
It is the level of the inside bottom of the pipe at a given point. Gravity drainage only works if invert levels fall continuously toward the connection point, so they are surveyed and recorded as the line is laid.
How is a drainage system tested?+
By an air or water test, as the specification states, on stacks and on below-ground sections before backfill or covering. The result is recorded per section and signed.
Do you build the external sewer line to the street?+
Building drainage and the external network are separate scopes. External lines fall under an underground utilities package, and the offer states exactly where the building drainage ends.
Why do floor drains need a trap seal?+
The water in the trap blocks sewer gas from entering the room. In a drain that is rarely used the seal can dry out, so the design may call for trap primers or a routine to top them up.
Who supplies Sanitary Drainage & Sewerage Piping in Saudi Arabia?+
NLS Contractors (Northlane Solutions Company) supplies Sanitary Drainage & Sewerage Piping across Saudi Arabia, including Riyadh, Jeddah, Dammam and Jubail. Send your specification and quantities to info@nlscontractors.com or info@northlanesolution.com for a quotation.