ᐅ Install the vapor barrier afterward—how should the vapor barrier film be covered?

Hello,

I noticed that in an unheated attic room, no vapor barrier was installed. The insulation consists of mineral wool fitted between the rafters and the room is finished with wooden panels. I became aware of this because the room develops a slightly sour smell when there are strong temperature fluctuations outside.

Question: Could I keep the wooden panels, install vapor barrier sheets, seal them at the walls, and then cover the sheets with new panels to finish? This would have the advantage that the existing panels would provide a solid substructure and allow for an optimal seal of the vapor barrier at the walls.

I would appreciate any advice.

Best regards,
Hansi 65

Hi,
how is the room being used?
Storage room?
Is the room in the attic or the loft?
Are there more rooms there?
If yes, how were they finished?

Please describe in detail.....

Best regards

Hello,

the room is located in the attic and has three walls made of masonry; the fourth side is a sloping roof that transitions into a short ceiling section, with the attic space above. The adjacent rooms are heated. We store drinks and toys in this room, and it is used several times a day. The rest of the sloping roof, ceiling, and attic have vapor barrier foil.

I will remove the wooden panels, install a vapor barrier, and attach the foil to the substructure using thin battens. The gap that forms between the foil and the panels may help to dry any condensation.

Regards, Hansi 65