Is a structural engineer required for facade demolition?

Hello,
we, together with other neighbors, have problems with the facade, which is built in timber frame construction.
The exterior facade (exterior plaster and "chipboard") must be removed; wooden beams and inner chipboard remain in place.

Now, the construction company commissioned for the execution says that a structural engineer must calculate whether the facade can be torn down for three adjoining houses. The building regulation in Hesse would require this, whereas in Bavaria, for example, it does not.

Is that really the case?
For other renovated, identical houses, this calculation was not carried out.
Especially since only one side is renovated at a time anyway.

And wouldn't this "calculation" have been possible to carry out in advance based on the construction plans? The construction company says it was not clear which chipboards were installed.
It just seems to us that the construction company failed to check this in advance or unnecessarily ordered the structural engineer, whom we ultimately have to pay for. The construction has now been halted because of this "calculation" for 6 working days ....

Thank you,
A person affected by ABG

Hello ABG-affected person,

if I have understood correctly, these are three adjoining houses (terraced houses) built with a timber frame construction. This is probably the type which is called Holzrahmenbauweise here in Lower Saxony.

As building owners, did you not receive any structural calculation for your houses? I assume that you have also paid for it.

First of all, it should be noted that each of these terraced houses must be spatially braced individually (also without the neighboring houses).
Basically, from a structural point of view, the sheathing serves the spatial bracing of the building. If there is a corresponding structural proof in the static calculation, it shows which wall elements exactly serve the bracing and which can possibly be opened.
However, it is unlikely that the sheathing on an outer wall may be completely removed without further measures. These measures usually have to be proven structurally in order not to endanger the stability of the building.

Usually, OSB boards (a type of chipboard) are used for the sheathing in timber frame construction. Unfortunately, I cannot make a remote diagnosis.

I am happy to answer any further questions.

Kind regards
Danton

Engineering and Planning Office
Dipl.-Ing. Thomas Brandenburg
Consulting Engineer and Building Surveyor
Insurance Specialist (Building Contract)

Hello, the purchase was several years ago, and currently I cannot find any documents related to structural calculations. Is it really the case that in Hesse a structural report is mandatory for this type of construction work, but not in Bavaria? Oh yes, "our" houses were also already on television, all because of the same construction defects. The "nice" ABG-Frankfurt...

Hello ABG victim, by the way, it would be nice to know your name as well, but I can understand if you want to remain anonymous.

Well, those are some nice conditions up there in northern Frankfurt, I briefly watched two of the videos. I had not heard of this case before.

From your first report, I mistakenly understood that you had the houses built yourselves at the time. Unfortunately, it is often the case that not all documents belonging to the building are handed over to the buyer when purchasing a house. Therefore, it is quite possible that you did not receive a structural calculation.

From my professional practice, I am not familiar with any other way than that for every intervention in a building that affects the structural system, a corresponding structural safety certificate must also be provided. I do not know the state building codes of Hessen and Bavaria in detail, but this is certainly no different in Bavaria than in Hessen. Here it is certainly not about a structural expert opinion, but rather about a structural proof for the planned construction state, namely the renewal of the facade. Such a renovation measure is not necessarily subject to approval and must accordingly be submitted to the responsible building authority. The structural proof in such a case serves the safety during the construction phase, as the executing company must also assume liability for this. Should a collapse occur during the renovation work without this structural proof, the company would act with gross negligence and would have to bear the costs for the damage incurred.

However, in the two TV broadcasts (Hessen 3 and RTL) far greater building damage was seen than just the mentioned chipboards. There the entire timber frame construction will certainly have to be renewed (which ultimately means the complete outer wall), since the timber stud construction has also been infested by dangerous fungi and has already rotted in large areas. Are the defects in your house less severe and what about the inside of the outer walls and the interior walls?

In a timber frame construction, as in other wooden constructions, it is essential from the outset to ensure that no moisture can penetrate the construction, neither from the outside nor from the inside. Unfortunately, there is a great potential danger here. Leaks in the facade or damaged vapor barrier foils on the inside are just two examples.

From whom did you purchase the house at the time? If you are very lucky, the previous owner may still have kept documents. Another possibility would be to inquire at the responsible building regulatory office. But keep in mind that there may be some entanglement with the city-owned ABG.

How about if a delegation of all those affected (collecting signatures) once contact the Mayor of the City of Frankfurt, with all due politeness, of course. Such a route via the political level sometimes works wonders. As a city-owned housing developer, the ABG ultimately also falls within his area of responsibility.

If it should ever come to the point that ABG has to cover the costs for the resulting building damage, then it will also be obliged to cover the costs for the necessary structural proofs.

I hope this has helped a little.

Best regards
Danton

Engineering and Planning Office
Dipl.-Ing. Thomas Brandenburg
Consulting Engineer and Building Expert
Insurance Specialist (Building Contract)

Hello ABG victim,

yes, that is indeed a big dilemma.

If Ms. Mayor Petra Roth sits on the supervisory board of ABG, she certainly has some influence on the actions of this company. She certainly does not sit there alone, but together with others, probably also members from the works council as well as the union, but the supervisory board members are supposed to "supervise" this company.

Also with regard to upcoming election results, she, like the other supervisory board members, should use her influence in this company in favor of the victims. But maybe they are already doing this as much as they can, who knows. On the other hand, she probably also has to represent the (financial) interests of the city of Frankfurt there, which presumably has a stake in this company.

Best regards Danton

.... On the other hand, she presumably also has to represent the (financial) interests of the city of Frankfurt there, which is likely involved in the company. Best regards Danton

I also thought Mrs. Roth would assert her influence and the executing construction company Frankfurt Holding would admit their obvious and serious mistakes. BUT NOTHING! Everything is being and was denied; in the newspaper, the managing director Mr. Junker lets it be written that the homeowners caused the water damage (even at a height of 6m) themselves by installing outdoor lamps ... Here is a current picture of the damage, the homeowner did not expect it to be this bad: The existing mold can penetrate almost unhindered into the interior due to the leaky vapor barrier. And don't forget, small children also live in the 32 affected houses ...