Hello,
If this is the wrong section, please move it!
We bought an older house built in 1971 about 7 years ago. At that time, the bedroom ceiling was repainted and the walls were wallpapered.
Over the years, we have noticed some fogging – meaning the walls have become slightly darker. The painter plans to repaint them again this summer.
Our flat roof was renovated 12 months ago.
Inside, there were never any signs of damp spots, but on the outside, just below the gutter, we could see concrete drips through the plaster, which is why we decided to renovate it.
Now, by chance due to a new lamp, I have noticed light spots on the bedroom ceiling. When I tap on them, they sound hollow. In the bedroom, I find about 7 of these spots spread over 15 sqm (160 sq ft) – each no larger than the width of a hand and scattered. In the other rooms upstairs, we do not have this fogging issue; the ceilings there still look freshly painted. However, even there, when tapping, I can occasionally find a few small hollow spots by chance.
There are no cracks or dark discolorations anywhere on the upper floor.
Could it theoretically be that the roof was more leaky than we thought, causing the reinforcement in the concrete to rust and therefore the plaster to sound hollow in small areas? Or is it more likely just a harmless cause such as old plaster, poor adhesion, or something similar?
I hope it is the latter, because otherwise, we would expect not only small hollow spots but rather longer, larger areas and also cracks in the plaster in these spots, right?
Pictures are really difficult to capture; even in person, you only notice the spots when looking closely.
If this is the wrong section, please move it!
We bought an older house built in 1971 about 7 years ago. At that time, the bedroom ceiling was repainted and the walls were wallpapered.
Over the years, we have noticed some fogging – meaning the walls have become slightly darker. The painter plans to repaint them again this summer.
Our flat roof was renovated 12 months ago.
Inside, there were never any signs of damp spots, but on the outside, just below the gutter, we could see concrete drips through the plaster, which is why we decided to renovate it.
Now, by chance due to a new lamp, I have noticed light spots on the bedroom ceiling. When I tap on them, they sound hollow. In the bedroom, I find about 7 of these spots spread over 15 sqm (160 sq ft) – each no larger than the width of a hand and scattered. In the other rooms upstairs, we do not have this fogging issue; the ceilings there still look freshly painted. However, even there, when tapping, I can occasionally find a few small hollow spots by chance.
There are no cracks or dark discolorations anywhere on the upper floor.
Could it theoretically be that the roof was more leaky than we thought, causing the reinforcement in the concrete to rust and therefore the plaster to sound hollow in small areas? Or is it more likely just a harmless cause such as old plaster, poor adhesion, or something similar?
I hope it is the latter, because otherwise, we would expect not only small hollow spots but rather longer, larger areas and also cracks in the plaster in these spots, right?
Pictures are really difficult to capture; even in person, you only notice the spots when looking closely.
guckuck2 schrieb:
If you’re feeling restless, open one of those spots and take a look.
If you don’t find anything interesting, you can always thank your neighbor with a nice rumor ;-)No, the ceiling still looks fine. If you say it’s nonsense, then I’ll leave it as is. Especially since I noticed this morning that there are also these small hollow spots on the ground floor.So again, if the reinforcement was damaged, there would have to be cracks on the roof and water ingress, and I should at least see water stains, cracks, or spalling on the inside of the ceiling, right? Because rust expands?
