ᐅ Plaster bulging / continuous plaster crack around the surface
Created on: 13 Sep 2025 07:12
M
MarcomitZehM
MarcomitZeh13 Sep 2025 07:12Hello everyone,
at my detached house built in 2004/2005, the first signs of plaster damage are slowly appearing. The exterior walls of the building are made of aerated concrete, and the columns are also glued aerated concrete. According to the documentation, the base area has a "colored stone plaster No. 900 with 3 mm (1/8 inch) grain size" applied, while the house wall has a "Terrastar 222 light disc plaster, 3 mm (1/8 inch)". I have two specific situations to discuss:
1. At the entrance area, there is a tiled stair landing covered by a porch supported by two columns. On one of these columns, the plaster has bulged and flaked off at one corner—oddly, this is on the inside of the pillar, facing the center of the stair landing, not on the outside exposed to the weather. As the photos show, there is a reinforcing mesh underneath the top coat of plaster. Using a utility knife, I can carefully cut around 3 cm (1¼ inches) beneath the surface, and the plaster there is also loose. The fact that the plaster bulges outward this way suggests that it is not simply due to someone bumping against the pillar; there seems to be another cause. Splashing rain also seems unlikely since this is an inner location… What could be the causes of this plaster detachment, and what would a professional repair look like? This is the only place on the entire house where the plaster has bulged like this. (There is another tiny plaster chip the size of a fingernail at a corner of the house, but that is clearly mechanical damage and, I believe, can simply be patched up without any special treatment.)
2. At the transition between the ground floor and the upper floor, there is a horizontal crack in the plaster. This crack is visible in several locations all around the building, sometimes quite noticeable, sometimes barely perceptible, always at exactly the same height. To me, it looks like the building itself has shifted here. The floor slab between the two floors is 20 cm (8 inches) reinforced concrete. The cracks are very thin, only hairline cracks, but it is visible that the plaster is detaching here—possibly due to water running underneath the plaster? What could be the causes of these hairline cracks, and does this require any repair? If yes, what would a proper professional repair entail?
Thank you very much, and best regards,
Marco
at my detached house built in 2004/2005, the first signs of plaster damage are slowly appearing. The exterior walls of the building are made of aerated concrete, and the columns are also glued aerated concrete. According to the documentation, the base area has a "colored stone plaster No. 900 with 3 mm (1/8 inch) grain size" applied, while the house wall has a "Terrastar 222 light disc plaster, 3 mm (1/8 inch)". I have two specific situations to discuss:
1. At the entrance area, there is a tiled stair landing covered by a porch supported by two columns. On one of these columns, the plaster has bulged and flaked off at one corner—oddly, this is on the inside of the pillar, facing the center of the stair landing, not on the outside exposed to the weather. As the photos show, there is a reinforcing mesh underneath the top coat of plaster. Using a utility knife, I can carefully cut around 3 cm (1¼ inches) beneath the surface, and the plaster there is also loose. The fact that the plaster bulges outward this way suggests that it is not simply due to someone bumping against the pillar; there seems to be another cause. Splashing rain also seems unlikely since this is an inner location… What could be the causes of this plaster detachment, and what would a professional repair look like? This is the only place on the entire house where the plaster has bulged like this. (There is another tiny plaster chip the size of a fingernail at a corner of the house, but that is clearly mechanical damage and, I believe, can simply be patched up without any special treatment.)
2. At the transition between the ground floor and the upper floor, there is a horizontal crack in the plaster. This crack is visible in several locations all around the building, sometimes quite noticeable, sometimes barely perceptible, always at exactly the same height. To me, it looks like the building itself has shifted here. The floor slab between the two floors is 20 cm (8 inches) reinforced concrete. The cracks are very thin, only hairline cracks, but it is visible that the plaster is detaching here—possibly due to water running underneath the plaster? What could be the causes of these hairline cracks, and does this require any repair? If yes, what would a proper professional repair entail?
Thank you very much, and best regards,
Marco
Similar topics