The PREMO BML SW wall duct module is used to install INLAP fire dampers in single-sided planked shaft walls and thus forms the optimum interface between the ventilation and drywall construction trades.

It consists of a plasterboard housing with integrated intumescent insulation. The module is adapted to the planking of the shaft wall and to the dimensions of the air duct and its insulation.

In the event of a fire, the INLAP fire damper installed in the ventilation duct closes the ventilation cross-section. At the same time, the insulation of the ventilation duct melts. The intumescent layer inside the PREMO BML wall duct module expands, closing the annular gap between the separating component and the air duct and thus limiting heat transfer to the side facing away from the fire.