I have a problem with the inside of a wall in the basement level. The wall faces south. It consists of painted plaster on the outside (original from 1977) and is built of Siporex (lightweight concrete) with plastered and painted inside. 2/3 of the wall was then below ground level.
When we bought the house almost 2 years ago, the wall was wallpapered with fabric and painted. At that time, all the interior plaster was only held in place by the wallpaper on the part that was below ground, so when I tore off the old wallpaper, all the plaster came off on 2/3 of the wall.
A construction company we hired plastered the wall again (with gypsum plaster) and repainted with regular paint. It only took three to four months before the plaster started falling down.
I then first removed the planting that was against the wall on the outside, which was blocking the drainage (Platon), and since then, the wall has been "open" with no contact with the ground.
I scraped off all the gypsum plaster that was essentially loose, then primed and plastered with house fix since I wanted to be sure to get something that adheres properly to Siporex.
On the house fix, I then painted with silicate paint.
This has now held for a little over a year, but is now starting to come off again, and I have two approximately 20-30 cm cracks on the inside...
This is not an issue on any other wall in the house, only this one.
I think the underlying problem might be that there's a built-in balcony above, and that water is leaking into the wall from above somewhere.
The strange thing, though, is that both times, the first time with gypsum plaster and now with house fix, when it started coming off, it has done so in the middle of the wall, the center of the wall... If it were that water was leaking in, it should start coming off from the top, I think.
If it were absorbing moisture from the slab (which is of course below ground), it should come off from the bottom, not the middle of the wall...
There are no water pipes or other pipes in the wall.
The best solution would, of course, be to get insulation on the outside, but since there's a patio door in the wall, it could be a bit tricky to do it well. The balcony should probably also be scraped clean of asphalt and resealed...
But, the question is, could it be the primer I applied that is now causing it to come off again, that it is too dense and in some way causes the moisture to be trapped?
Again, just strange that it starts in the middle of the wall...
When we bought the house almost 2 years ago, the wall was wallpapered with fabric and painted. At that time, all the interior plaster was only held in place by the wallpaper on the part that was below ground, so when I tore off the old wallpaper, all the plaster came off on 2/3 of the wall.
A construction company we hired plastered the wall again (with gypsum plaster) and repainted with regular paint. It only took three to four months before the plaster started falling down.
I then first removed the planting that was against the wall on the outside, which was blocking the drainage (Platon), and since then, the wall has been "open" with no contact with the ground.
I scraped off all the gypsum plaster that was essentially loose, then primed and plastered with house fix since I wanted to be sure to get something that adheres properly to Siporex.
On the house fix, I then painted with silicate paint.
This has now held for a little over a year, but is now starting to come off again, and I have two approximately 20-30 cm cracks on the inside...
This is not an issue on any other wall in the house, only this one.
I think the underlying problem might be that there's a built-in balcony above, and that water is leaking into the wall from above somewhere.
The strange thing, though, is that both times, the first time with gypsum plaster and now with house fix, when it started coming off, it has done so in the middle of the wall, the center of the wall... If it were that water was leaking in, it should start coming off from the top, I think.
If it were absorbing moisture from the slab (which is of course below ground), it should come off from the bottom, not the middle of the wall...
There are no water pipes or other pipes in the wall.
The best solution would, of course, be to get insulation on the outside, but since there's a patio door in the wall, it could be a bit tricky to do it well. The balcony should probably also be scraped clean of asphalt and resealed...
But, the question is, could it be the primer I applied that is now causing it to come off again, that it is too dense and in some way causes the moisture to be trapped?
Again, just strange that it starts in the middle of the wall...
Common plaster and silicate paint on the inside....platonmat and drainage on the outside....
The Plato mat and drainage are already on the outside. As mentioned, I have removed all the soil that was against the wall, so it is no longer under the ground. The problem I understand with regular plaster mortar is that it reacts with Siporex. According to Weber, regular plaster mortar doesn't work; you have to use "Weber KC Putsbruk B" in that case, and as far as I understood, it is very coarse...
I was never able to find a retailer that had the KC mortar, and then I was advised to use "husfix," which was also supposed to work and which I then used... Apparently, it didn't work so well...
I was never able to find a retailer that had the KC mortar, and then I was advised to use "husfix," which was also supposed to work and which I then used... Apparently, it didn't work so well...
