ᐅ Is it acceptable to insulate an attic space without a vapor barrier?

Hello,

we bought a 5-year-old KfW 55 house. The attic space is unused, but it was insulated because of the gas heating system installed there by the previous owner. The loft is finished and inhabited. I have now noticed that the roof insulation in the attic space does not have a proper vapor barrier. A foil was nailed over the insulation wool, but it is not sealed.

Can this be left as it is?

Are you referring to insulation between rafters?

How is the upper floor ceiling constructed? Has a vapor barrier perhaps already been installed there, and was the attic insulated later as a DIY project to prevent the hot water tank from getting too cold? The heating system itself should not really introduce moisture into the loft.

NatureSys schrieb:

Is this about insulation between rafters?

Yes, exactly. The insulation directly beneath the roof tiles.

WilderSueden schrieb:

How is the upper floor ceiling constructed? Has a vapor barrier possibly already been installed there, with the attic insulated later as a DIY project?

The ceiling between the upper floor and the attic is also insulated, and I (hope) that a vapor barrier has been installed there as well.

Then I don’t really see a problem with that. Adding another vapor barrier on top would be nice, but it probably isn’t crucial.