ᐅ Air gap between exterior plaster and insulation – noticeable hollow sounds

Hello.

Our house was completed at the end of 2013. The external insulation and the exterior render were only applied in March 2014 due to weather conditions. From the beginning, tapping on the render produced a hollow sound, but I didn’t give it much thought.

After an accident on New Year’s Eve involving a neighbor’s firework, a part of the exterior render was damaged (see photos). It has now become visible that the render at this spot is about 1mm (0.04 inches) detached from the insulation/fiber mesh. This would also explain the hollow sound heard when tapping around almost the entire house.

A representative from the construction company visited and said everything was fine and that this was normal. Due to my own doubts and confirmation by somewhat knowledgeable acquaintances, I wanted to get an expert opinion here in the forum before possibly hiring a building inspector or lawyer.

In the end, do I now have to worry every time I maybe kick a heavy soccer ball against the wall that it will leave a hole in the render?

Thank you very much for your ideas and suggestions.

Best regards

KallederNeue