How to properly tape a vapor barrier?

Hello!

I have to admit I am a bit uncertain after reading various blogs and brochures on the topic of insulation. Maybe someone here can help me!

We are currently insulating our semi-detached house. The insulation between the rafters is already in place, and now I am waiting for the vapor barrier to be delivered.

From different sources, I have heard that the barrier should always be glued overlapping from top to bottom, while others say the exact opposite... does that really matter? Based on the information I have now, I would start from the gable and then always overlap and glue the upper foil over the next lower one.

Furthermore, I am not quite sure whether I should apply the insulation under the rafters before or after the vapor barrier?!

I would be very happy to receive an answer!

Thank you in advance!

Hello,

.. According to the information I now have, I would start from the gable and then always overlap and glue the upper foil over the subsequently lower one.

That is correct.

... Furthermore, I am not quite sure whether I should apply the insulation below the rafters before or after the vapor barrier?!?

The better solution is always when the vapor barrier is placed after the insulation below the rafters towards the interior of the room. That means the vapor barrier protects the "entire" insulation layer.

Best regards.