When we bought our 1.5-story house, the upper floor was unfinished, and in the ceiling of the lower floor, there is a puncture-resistant vapor-tight foil. But now that I'm finishing the upper floor, the foil has no function. Can it be removed? The reason is that otherwise you wouldn't see if there was a water leak from the upper floor. Better that it starts dripping from the ceiling than leaking into the walls without noticing anything.
How would you do it/have done it?
How would you do it/have done it?
quite right...
remove or puncture as best you can.
That plastic has no function when you expand the climate screen...
this is under the condition that you block on the new part and there is a satisfactory vapor barrier in the wall between the joists and rafters.
remove or puncture as best you can.
That plastic has no function when you expand the climate screen...
this is under the condition that you block on the new part and there is a satisfactory vapor barrier in the wall between the joists and rafters.
Perform a thread lift as I am in the same situation. I have a 1.5-story house where the vapor barrier in the attic floor will become the vapor barrier in the intermediate floor when the upper floor is completed. I can't find more threads on the subject, so I would like more opinions to be presented.
I myself am considering that one should perforate or remove the vapor barrier in the intermediate floor in all roof truss sections except where there are wet rooms on the floor below. Any moisture is still ventilated out on the sides via spaced paneling.
One thought I have is to cut the vapor barrier in the intermediate floor so that it can be folded up and connect to the new vapor barrier that runs in the sloping ceiling. Then there will be some splicing and taping between the trusses as the knee wall should be on the warm side.
Does that sound reasonable?
My reasoning as to why the vapor barrier should not remain in the intermediate floor:
1.) On the upper floor, I will have waterborne heating. I plan to have the intermediate floor fully insulated so that the underfloor heating does not leak to the lower floor and for sound insulation. Doesn't this make it even more important not to have vapor plastic under the underfloor heating? Then the ceiling below could be colder, and condensation could occur when the vapor plastic remains?
2.) The same condensation can occur in general as heat rises and the upper floor tends to be warmer than the lower floor?
3.) I also wonder how it will be when you lay parquet or laminate flooring on top of the underfloor heating. If you have vapor plastic and felt paper before the floor, would that also mean trapping moisture if the vapor barrier of the intermediate floor is still there?
Two other considerations:
Is there any risk of condensation water and mold during the construction period when you have perforated the vapor barrier of the intermediate floor and have not yet completed the vapor barrier of the upper floor, and there is no heat on the upper floor causing a significant temperature difference?
How about in the future in a completed house if you would like to have maintenance heating on the upper floor and full heating on the lower floor? Does condensation occur?
I myself am considering that one should perforate or remove the vapor barrier in the intermediate floor in all roof truss sections except where there are wet rooms on the floor below. Any moisture is still ventilated out on the sides via spaced paneling.
One thought I have is to cut the vapor barrier in the intermediate floor so that it can be folded up and connect to the new vapor barrier that runs in the sloping ceiling. Then there will be some splicing and taping between the trusses as the knee wall should be on the warm side.
Does that sound reasonable?
My reasoning as to why the vapor barrier should not remain in the intermediate floor:
1.) On the upper floor, I will have waterborne heating. I plan to have the intermediate floor fully insulated so that the underfloor heating does not leak to the lower floor and for sound insulation. Doesn't this make it even more important not to have vapor plastic under the underfloor heating? Then the ceiling below could be colder, and condensation could occur when the vapor plastic remains?
2.) The same condensation can occur in general as heat rises and the upper floor tends to be warmer than the lower floor?
3.) I also wonder how it will be when you lay parquet or laminate flooring on top of the underfloor heating. If you have vapor plastic and felt paper before the floor, would that also mean trapping moisture if the vapor barrier of the intermediate floor is still there?
Two other considerations:
Is there any risk of condensation water and mold during the construction period when you have perforated the vapor barrier of the intermediate floor and have not yet completed the vapor barrier of the upper floor, and there is no heat on the upper floor causing a significant temperature difference?
How about in the future in a completed house if you would like to have maintenance heating on the upper floor and full heating on the lower floor? Does condensation occur?