Houses with brick facades are at high risk of collapsing if they were built between the 1940s and 70s. Svensk Byggtjänst has so far only noted a number of collapses but warns that the problem may escalate and that homeowners and property owners face extensive renovation costs.
Svensk Byggtjänst estimates that there are 80 million square meters of brick facades built during the period 1940-1975. A large part of these may be at risk because they contain reinforcement and ties that are rusting.
Brick house facades have long been considered relatively maintenance-free. But new discoveries made by Svensk Byggtjänst show that there are significant problems with brick facades. They are at risk of collapsing or blowing apart due to the reinforcement in the walls or the ties, so-called cramps that hold the wall in place, rusting away. This mainly applies to properties with facades built from half-brick construction, 120 millimeters wide, which have become common since the 1930s. The brick walls are anchored to the building’s frame of lightweight concrete, concrete, or wood using steel cramps.
- What has happened now is that several inadequately anchored cavity walls have partially collapsed in connection with strong winds. The cramps that are supposed to secure the wall have often rusted or been inadequately fastened, writes Bosse Samuelsson, at Svensk Byggtjänst in a warning article about the problems with brick facades.
One explanation as to why this is happening now is that in the 50s and 60s, non-stainless steel cramps were used, which are now beginning to rust away. Some break completely, others are damaged so that the strength is reduced. Bosse Samuelsson also writes that walls are at risk of collapsing due to poor fastening, which can be caused by the brick courses not being level with floor slab edges and the cramps becoming too short and bending down in the air gap.
- Brick facades that are between 30 and 65 years old likely have problems with rusting reinforcement or tying. The facades need to be examined for cracks in the joints, mortar that has come loose, or where whole brick courses have changed position. These are signs that the joint reinforcement has rusted, writes Bosse Samuelsson.
The problems with the crumbling walls are not only economic. The costs to repair these can be high. There is a great risk of personal injury when being or carrying out work near such a facade. The area around the wall should be cordoned off and scaffolding must be anchored to an underlying wall. A structural engineer and a contractor with experience in similar work should be consulted.
According to Svensk Byggtjänst, all reinforcement will eventually experience corrosion when the pH value of the cement mortar drops from 12 to 9 through carbonation, which occurs when the calcium hydroxide in the mortar converts to calcium carbonate through oxygen in the air or dissolved in water. When cracks appear in the joints, water can penetrate to the reinforcement and accelerate corrosion. Water infiltration can also lead to frost spalling of the brick.
http://www.e24.se/branscher/fastighetbygg/artikel_439071.e24
Svensk Byggtjänst estimates that there are 80 million square meters of brick facades built during the period 1940-1975. A large part of these may be at risk because they contain reinforcement and ties that are rusting.
Brick house facades have long been considered relatively maintenance-free. But new discoveries made by Svensk Byggtjänst show that there are significant problems with brick facades. They are at risk of collapsing or blowing apart due to the reinforcement in the walls or the ties, so-called cramps that hold the wall in place, rusting away. This mainly applies to properties with facades built from half-brick construction, 120 millimeters wide, which have become common since the 1930s. The brick walls are anchored to the building’s frame of lightweight concrete, concrete, or wood using steel cramps.
- What has happened now is that several inadequately anchored cavity walls have partially collapsed in connection with strong winds. The cramps that are supposed to secure the wall have often rusted or been inadequately fastened, writes Bosse Samuelsson, at Svensk Byggtjänst in a warning article about the problems with brick facades.
One explanation as to why this is happening now is that in the 50s and 60s, non-stainless steel cramps were used, which are now beginning to rust away. Some break completely, others are damaged so that the strength is reduced. Bosse Samuelsson also writes that walls are at risk of collapsing due to poor fastening, which can be caused by the brick courses not being level with floor slab edges and the cramps becoming too short and bending down in the air gap.
- Brick facades that are between 30 and 65 years old likely have problems with rusting reinforcement or tying. The facades need to be examined for cracks in the joints, mortar that has come loose, or where whole brick courses have changed position. These are signs that the joint reinforcement has rusted, writes Bosse Samuelsson.
The problems with the crumbling walls are not only economic. The costs to repair these can be high. There is a great risk of personal injury when being or carrying out work near such a facade. The area around the wall should be cordoned off and scaffolding must be anchored to an underlying wall. A structural engineer and a contractor with experience in similar work should be consulted.
According to Svensk Byggtjänst, all reinforcement will eventually experience corrosion when the pH value of the cement mortar drops from 12 to 9 through carbonation, which occurs when the calcium hydroxide in the mortar converts to calcium carbonate through oxygen in the air or dissolved in water. When cracks appear in the joints, water can penetrate to the reinforcement and accelerate corrosion. Water infiltration can also lead to frost spalling of the brick.
http://www.e24.se/branscher/fastighetbygg/artikel_439071.e24
A few years ago (3, 5, 7? don't remember), a large part of the gable facade of a three-story high school building in Falköping collapsed. According to a source, this happened due to rusted wall ties and strong wind. My point in telling this is the following: Within a few years before, the facade had been inspected by a bricklaying company whose report was along the lines of "something must be done about this, or it might collapse." No action was ordered, and everything was fine until... well, you know what happened. Luckily, no seventh grader was walking the usual worn path on the lawn just under the facade when it came down (to my knowledge).
If this report from Svensk Byggtjänst had existed then, action would probably have been taken. It's good that more is coming out about this problem so that its seriousness can be more easily understood.
Best regards, MaxPax
If this report from Svensk Byggtjänst had existed then, action would probably have been taken. It's good that more is coming out about this problem so that its seriousness can be more easily understood.
Best regards, MaxPax
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