Know-It-All
· Västra Götaland
· 12 305 posts
You should indeed install a vapor barrier. There is an ongoing discussion about vapor barrier vs vapor seal, but both do the job.
I thought it looked like sheet metal in the picture in #1, but upon closer examination of the picture, it could just be concrete, even though I still find it difficult to determine. Right should be right.D Daniel 109 said:
If there's no sheet metal, then the situation is a bit better.
One advantage of a vapor retarder is that moisture can move down toward the "dehumidifier" that you say should be installed. With a "barrier," it's a stop. If you have cellulose, you benefit more from a vapor retarder than a barrier. Then, someone can argue differently as much as they want since there have always been two camps in this question. You can surely have someone come and measure how much the concrete counters since it is airtight but not a diffusion barrier. You certainly don't want less resistance in the floor compared to what is called the subfloor, (your concrete).
It's mostly your concrete that determines what you need above. Cellulose is perfectly fine, but there are also different vapor retarders and how much they should allow through. A retarder is always a retarder.
It's mostly your concrete that determines what you need above. Cellulose is perfectly fine, but there are also different vapor retarders and how much they should allow through. A retarder is always a retarder.
Should he dehumidify the residence with a dehumidifier in the crawl space? There is no advantage to letting moisture seep into the floor.
No, he should obviously dehumidify the crawl space, but since moisture from above gets there, wouldn't it be good to check? Moisture is drawn towards the colder part... Are we agreed there? Now you're suddenly reversing your previous statements?...D Daniel 109 said:
If the user has a vapor retarder and underfloor heating, then it should be the best...
"But I'm saying that he should test the inertia in the concrete so that moisture doesn't remain in the insulation." This applies whether you set a barrier or a retarder.
Know-It-All
· Västra Götaland
· 12 305 posts
With underfloor heating, the room will be cooler than the floor, so moisture will be drawn both upwards and downwards from there. I think a vapor retarder is good here because the permeability of the concrete is unknown. If it's just regular concrete, it doesn't matter whether you use a vapor retarder or a vapor barrier. But the vapor retarder is more expensive, so you can save a bit.
The concrete is more permeable than a moisture barrier in any case. A moisture barrier will work. Probably the regular flooring is sufficient.
The final floor will probably be glued if it makes any difference. Glued oak parquet laid on a kind of renovation floor that is on top of the subfloor chipboard.
Bought a vapor barrier at Bauhaus with universal tape! Feels good.
Bought a vapor barrier at Bauhaus with universal tape! Feels good.
It will surely be fine.
Buying vapor barriers and tape in Sweden is expensive... And of course, you have to follow the recommended info... You splice and tape.. If you want a good price on everything, PM me and you'll see that you can probably get away with 40% of the cost compared to buying from them at the building store..
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