ventelinjer

Ventelinjer are a component of a building’s plumbing and drainage system designed to vent air and sewer gases from the interior while allowing wastewater to drain freely. They help maintain proper pressure within the drainage network and protect trap seals from being siphoned by draining fixtures.

Function and operation: When water flows through the drainage pipes, it can create negative pressure behind it. Ventelinjer provide a path for air to enter the system, which stabilizes pressure and prevents traps from losing their water seal. They also carry sewer gases safely above the living spaces, typically to a vent stack that terminates on the roof or to an approved outdoor outlet. In some systems, mechanical devices such as air-admittance valves may be used as an alternative to traditional vent pipes, though they have specific limits and applications.

Types and configurations: Common forms include vent stacks or stacks that rise vertically to the roof, branch vents that connect from individual fixtures, and circuit or home-run vent lines that serve multiple fixtures. In modern plumbing, materials such as PVC, ABS, or metal are used for vent lines, depending on local codes and system design. Air-admittance valves provide a one-way venting option inside the building envelope in certain jurisdictions.

Installation considerations: Ventelinjer must be properly sized and connected to the drainage system, with an unobstructed path to the outdoors or roof. They should maintain appropriate elevation relative to fixtures and avoid horizontal sections that can collect condensate. Local building codes regulate minimum diameters, placement, and vent terminations.

Maintenance and safety: Regular inspection is advised to prevent blockages from debris, ice, or buildup. Blocked vents can cause odors, poor drainage, and increased pressure on the system.

See also: drainage system, trap, vent stack, air-admittance valve.