Facade insulation with mineral foam boards?

Hello everyone,
We are currently new owners of a single-family house built in 1954 with 0% insulation.
After our conversation with the energy consultant, he advised us, among other things, to install a façade insulation with 16cm mineral foam boards.

Does anyone have experience with this type of insulation? Costs? Necessity?
Or does anyone have general long-term experience with the insulation of an old building with (30cm clay aggregate bricks)? Or is it better to forego façade insulation?

Thanks in advance
Regards, Manuel

Does anyone have experience with this type of insulation? Costs? Necessity?

I think it's the cheapest variant with the worst insulation values. The energy consultant can definitely tell you the costs.
Is an ETICS necessary? I would always do it in the context of a major renovation if you also want to address the facade. But first insulate the ceiling floors and upgrade the windows.

Or does anyone generally have long-term experience with insulating an old building with (30cm expanded clay bricks)?

It’s done every day – and has been for many years. Both in old buildings and new buildings, there are no fundamental differences.

My question would be why the energy consultant suggests this insulation variant. I am insulating my old building in the next few months as well, but I’m using a different material with significantly better insulation values. 12cm is enough to easily achieve KFW 55 level walls. But it costs a bit more (however, for example, the roof overhang does not have to be enlarged).

My question would be why the energy consultant suggests this insulation variant

He said it is a bit more expensive but later no hazardous waste

I am insulating my old building in the next few months as well

Are you installing a ventilation system (decentralized)

He said it was a bit more expensive but later not hazardous waste

So expensive, worst insulation properties (WLG 42 or 45) – but a clear conscience? How can you even comply with the Energy Saving Ordinance with that?

Are you installing a ventilation system (decentralized)

Yep! Already had a central controlled residential ventilation system in the last house. I never want to miss it again. Now, however, "only" decentralized. Model RL50RAS from Raumluft Shop.

There is an article from the Fraunhofer Institute stating that modern ETICS systems are recyclable, so not hazardous waste. We just insulated with EPS (so Styrofoam). I think it is even more environmentally friendly than mineral wool, even if the feeling suggests otherwise. What shocked me was that small Styrofoam pieces are now and probably forever scattered all over the garden.