House from -48 (plank walls) that will be extended and then have an additional floor added. The constructor has specified that the interior walls (plank walls) on the ground floor should be covered with a vapor barrier, then have studs added (45s + insulation) and then a new surface layer. The walls should also be externally insulated (2x75 I believe).
In itself, that's no problem, but what I'm wondering about is how to achieve a continuous vapor barrier with the upper floor. If I've understood correctly, you apply the vapor barrier around the entire house so to speak. But how do you handle the intermediate floor?
From what I've read, there are really two ways to build on old houses (vapor barrier or no vapor barrier) - either do it with plastic by the book, or not use plastic at all - and since we've decided to go the plastic route (we trust the constructor here), we want it done correctly so we don't miss or overlook anything.
We will have contractors, but since the extension will likely happen in two steps (ground floor first and upper floor afterward), I'm wondering what we should consider. It may be different contractors doing the first and second steps.
Thanks in advance
In itself, that's no problem, but what I'm wondering about is how to achieve a continuous vapor barrier with the upper floor. If I've understood correctly, you apply the vapor barrier around the entire house so to speak. But how do you handle the intermediate floor?
From what I've read, there are really two ways to build on old houses (vapor barrier or no vapor barrier) - either do it with plastic by the book, or not use plastic at all - and since we've decided to go the plastic route (we trust the constructor here), we want it done correctly so we don't miss or overlook anything.
We will have contractors, but since the extension will likely happen in two steps (ground floor first and upper floor afterward), I'm wondering what we should consider. It may be different contractors doing the first and second steps.
Thanks in advance
Hello .. The vapor barrier or plastic must not be inside the wall; it should be closest to the surface layer..
if the plastic is 5 cm inside the wall, the heat will condense there and it will mold..
In between the joists you don't need plastic since you have full heat on the upper floor, but the ceiling on the upper floor should be covered with plastic.
Eti..
if the plastic is 5 cm inside the wall, the heat will condense there and it will mold..
In between the joists you don't need plastic since you have full heat on the upper floor, but the ceiling on the upper floor should be covered with plastic.
Eti..
You can indeed place the "Ångspärren eller plasten" inside the wall. However, it should be on the warm side of the wall. It is excellent to place the ångspärren or plasten and then the 45:an. This way, you get an installation space for wiring, junction boxes, etc., and there are minimal holes in the ångspärren or plasten.
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they did this in a residential area in the neighboring municipality and all the houses had problems, as water ran along the walls on the floor. so I know that ... But if you put a 15 mm plywood and then the drywall, then you don't puncture the plastic so easily and you have something to screw and nail into.. I would never personally place the plastic inside the wall and therefore I don't want others to make that mistake.
Regards
Eti..
Regards
Eti..
It entirely depends on the thickness of the wall. The plastic may sit a maximum of 1/3 into the wall. So if you place a 45mm piece, you need at least 90mm of insulation outside.
So in your case, if you have the plastic 45mm in from the inside and have 2*75mm outside, it's fine. However, if you only put 75mm, there's an increased risk of condensation problems (I'm not quite sure how it would be with a plank wall). And if you only add insulation on the inside, you would likely have problems with the plastic 45mm into the wall.
In the intermediate floor, you don't have plastic since you have warmth on both sides. It's only the outer shell that has a plastic layer.
So in your case, if you have the plastic 45mm in from the inside and have 2*75mm outside, it's fine. However, if you only put 75mm, there's an increased risk of condensation problems (I'm not quite sure how it would be with a plank wall). And if you only add insulation on the inside, you would likely have problems with the plastic 45mm into the wall.
In the intermediate floor, you don't have plastic since you have warmth on both sides. It's only the outer shell that has a plastic layer.
Just the thought that there would be an increased risk of condensation problems if the plastic is misplaced, then surely you're not so foolish to take that risk and place the plastic inside the wall.
A lottery with a great risk of negative consequences later. And who is the one paying if it goes wrong, and everything has to be redone... It is proven that placing the plastic closest to the surface layer means you definitely don't make a mistake.
I have seen so many building errors and had to fix issues caused by others who mess things up for people.
Just look at the single-layer-sealed houses, how well did that work out, even though it was an approved building standard? My first impression when I saw this was, what an idiocy.
And who stands there now and will get a big hole in their wallet...
and feels completely fooled. ????
Eti..
A lottery with a great risk of negative consequences later. And who is the one paying if it goes wrong, and everything has to be redone... It is proven that placing the plastic closest to the surface layer means you definitely don't make a mistake.
I have seen so many building errors and had to fix issues caused by others who mess things up for people.
Just look at the single-layer-sealed houses, how well did that work out, even though it was an approved building standard? My first impression when I saw this was, what an idiocy.
And who stands there now and will get a big hole in their wallet...
and feels completely fooled. ????
Eti..