Hello.
I'm putting on my dunce hat right now so it's done. Done!
After renovating a small room, I've discovered moisture stains along one of the seams in our new Huntonit ceiling. (Picture attached) The ceiling is on the second floor, and we have an unheated attic above that's partially insulated. My first concern was that we had a leak from the outer roof (old paper).
After a look in the attic, I confirmed that there's moisture at the specific spot between the ceiling and the moisture barrier. (Picture attached). You can clearly see condensation drops. As I remember it, I placed the vapor barrier from below and attached it to the existing sparse framework. Then I put the ceiling boards tightly against the plastic. So, correct me if I'm wrong, but have I now created a risky construction?
Is it best to tear down and redo?
Regards,
/Fredrik
I'm putting on my dunce hat right now so it's done. Done!
After renovating a small room, I've discovered moisture stains along one of the seams in our new Huntonit ceiling. (Picture attached) The ceiling is on the second floor, and we have an unheated attic above that's partially insulated. My first concern was that we had a leak from the outer roof (old paper).
After a look in the attic, I confirmed that there's moisture at the specific spot between the ceiling and the moisture barrier. (Picture attached). You can clearly see condensation drops. As I remember it, I placed the vapor barrier from below and attached it to the existing sparse framework. Then I put the ceiling boards tightly against the plastic. So, correct me if I'm wrong, but have I now created a risky construction?
Is it best to tear down and redo?
Regards,
/Fredrik
Hello.T TheGame said:
Yes. True. That is surely the reason for the condensation because it becomes too tight between the ceiling and the vapor barrier. Old insulation exists in the attic (terraced house from -68), and in the room where we put a new ceiling and plastic, there was no vapor barrier before...
/F
There is good ventilation with airflow from one side to the other...Jonatan79 said:
Vents in all rooms on the upper floor and a fan with constant flow in the bathroom.
There is moisture (condensation) between the inner ceiling and the plastic. My suspicion is that there is a minimal gap between the ceiling panels where indoor air (humid and warm air) rises. The moisture does not reach the insulation in the attic.
It will mean taking down the inner ceiling, removing the plastic and battens, and then installing new plastic, new battens, and the inner ceiling in the correct order...
But hey… if warm indoor air condenses behind 10 mm ceiling tiles - you have a very cold surface there. I would double-check the insulation/thermal bridge above in the attic. Make sure the plastic is not cold, instead of trying to "ventilate away the problem".F Frippego said:
You solve that with sufficient insulation
This which one is worried about, putting plastic instead of the vapor barrier that has been in place since old times. May I ask what kind of insulation and how thick the insulation you have/had in the attic when this condensation problem occurred? I currently have 150mm thick rock wool insulation in the cold attic and 130mm in the wall towards the knee wall attic.
I actually don't know what type of insulation is in the attic. It's from when the house was built and is probably not the best compared to today's options. I would guess it's about 125mm. It has thin paper on both sides...