Dirty or open duct ends
If ducts remain open during the construction phase, dust and debris get inside. This will later be blown into the rooms.
Ventilation ducts installed: check before insulation or drywall
The ducts for the mechanical ventilation system often lie on the bare floor — under the future insulation — or on the ceiling. A ventilation system runs every day for 20 years. Whether it runs quietly, efficiently and hygienically is decided now. After insulation or drywall, you will only see the valves.
The most common expensive defects in ventilation ducts
Tight bends and crushed flexible ducts
Every crush increases resistance. The system gets louder and does not reach the planned air volumes.
Missing insulation in cold areas
Uninsulated ducts in unheated areas form condensation. Missing or interrupted insulation causes moisture damage in the ceiling.
Ducts only pushed together instead of engaged
Connections must be fully seated. Half-inserted ducts lose air and reduce performance.
What you should document and check now on ventilation ducts
Count outlets and record duct routing
Count the supply and extract outlets per room and compare them with the plan. Also photograph the routing back to the manifold.
Photograph connections and bends in detail
Take close-ups of all push-fit connections as well as tight or crushed changes of direction.
Check insulation and wall penetrations
Photograph where the ducts are insulated and how they pass through walls and ceilings.
Check sealing of duct ends
Photograph whether open ends are sealed during the construction phase.
Before the covering goes on
Upload your photos – duct routing, connections, and insulation will be systematically checked for typical installation errors.