Recognizing potential risks of balcony collapse: What indicators should I look out for?
Incidents like the recent one in Hamburg demonstrate: When balconies give way, it's potentially lethal. An expert discusses how to spot signs of damage and when a balcony is past its load-bearing limit.
A balcony suddenly collapsing downwards: Such a terrifying situation claimed a life in Hamburg mid-August, with five more victims tumbling several meters. Authorities are probing the tragedy's cause. Looking at your own balcony, you might now ponder: How can you ascertain if a balcony is about to fail?
In the words of Professor Norbert Gebbeken, President of the Bavarian Chamber of Engineers-Building, such unfortunate incidents are relatively infrequent. However, the not-so-encouraging fact is that it's typically challenging for tenants or homeowners to detect potential harm around their balcony.
"Naturally, you can always examine if moss or algae are developing on balconies. That suggests moisture may be seeping into the structure," says Gebbeken. However, given that balconies are usually adorned with tiles or some kind of covering, it's pretty difficult for tenants and owners to pinpoint what's happening below.
Cracks are more apparent from below
Cracks in the balcony are usually visible from below the balcony, for instance, by those standing on their balcony one floor below. They serve as a telling sign. "If a crack is conspicuous on the commonly-used cantilevered reinforced concrete slabs, it's generally too late," says Gebbeken. In that case: stay off it, alert your landlord, or as the owner, consult specialists in structural damage - such as building inspectors.
The engineering chambers maintain registers of experts. "They possess experience, know where to look, have moisture meters, and cameras that can peer into cavities," says Gebbeken.
It's also advisable to seek experts' guidance if specific components of wooden balconies display deformation or appear slightly skewed.
Caution when setting up pools
Prevention is always the best medicine: Although German homeowners are not required to have their balcony inspected regularly without a specific reason, Gebbeken advises having it inspected by experts every ten years, as per the VDI 6200 guideline of the Association of German Engineers. "When the balcony is utilized not just by tenants, but also for purposes like a restaurant or the like, it should be inspected every three to five years," says Gebbeken.
And the residents can step in too: Ensure you're not overloading your balcony. They're typically designed to hold 350 to 500 kilograms per square meter. "That means that four, five, six, or even seven people can comfortably stand on a single square meter of balcony. But they wouldn't all fit on one square meter at once," says Gebbeken. "Routine usage of a balcony by people should, therefore, not pose a problem." However, it becomes tricky if, for example, a wading pool is set up. "Then it becomes difficult as we quickly surpass these loads," says the structural engineer.
By the way, a balcony's load-bearing capacity can be gauged from the static calculations for the building. These are generally accessible to homeowners.
Based on Professor Gebbeken's advice, if you notice cracks on your balcony from below, it's crucial to stay away, alert your landlord, or consult structural damage specialists. Additionally, it's advisable to seek their expertise if any wooden balcony components show signs of deformation or slight skewing.
