Is it still possible to plan house construction now?

I can't confirm that at all. No idea in which dystopian world you live. The construction sites are well visited and new construction projects have also been starting here regularly for several weeks and are progressing quickly. And I am talking about the Berlin and Potsdam area as well as personal experiences from new development areas in Düsseldorf and Neuss.

I can confirm that. Our shell construction company, for example, has only made new contracts (but already since last year) with price escalation clauses for steel and concrete. They see no problem in timely material procurement and still agree to a contractual completion date with late penalties today. They would hardly do that if nothing could be predicted or planned at all. Here in the area, a large public construction project was indeed recently postponed for at least 1 year due to the current situation. But we are talking about completely different quantities and backgrounds there. Edit:

Do you have enough reserves to cover both the due loan installments and the previous rent and significantly increased material costs?

Since unforeseeable price increases were already the order of the day last year due to Corona, we have planned a solid buffer. I would actually not recommend anyone to plan completely at the limit today.

What of course interests me is, when you sign the contract with a construction company, somehow plan a move-in date and have also signed the loan agreement, and then for whatever reason it is delayed, let's say due to unavailable roof tiles.

Do you have enough reserves to cover both the due loan installments and the rent so far and significantly increased material costs?

If we assume the worst case.

So I already have two construction companies with whom I would sign a turnkey construction contract at a fixed price. Admittedly, that is not cheap right now, but it is a fixed price. Therefore, increased material costs do not interest me at all. We could financially absorb construction delays and the resulting double burdens, yes.

So now you’re not building because the future seems too uncertain to you. In recent years you couldn’t build because prices exploded and it was unclear how much further they would rise.
In the future, you won’t build either because the value of the house might go down again after the boom phase.

There will always be reasons that you find yourself!!! not to do things. It doesn’t necessarily have to be about building a house.

The fact is at least that supply chains are disrupted, but it is not foreseeable that everything will go downhill. Who really cares about Ukraine or Russia on the global market? Those are not relevant countries. Sad but true.
In addition, there are historically low interest rates. Doesn’t matter if the rates are now at 1.0 or 2.3% – historically, 4% is the average. If you can’t handle 1% more interest, you just have to build a bit smaller and cut back. Our parents already knew how to do that. Here you always read about a single-family house for 2 people with 180 sqm, double garage, KNX, etc.
Is that really necessary?

Conclusion: You can still build well, but you have to calculate reasonably and safely.

Contracts are, as mentioned, one thing, their fulfillment another.

In the automotive sector, the situation currently is that while the purchase contract from the manufacturer regarding the purchase price is being honored, the delivery date is not. In the case of an accident or a major repair, there are simply no vehicles available on the market. And it is becoming increasingly difficult, if not impossible, to procure replacements here.

Vehicle manufacturers simply cannot produce. Precisely because parts come from the insignificant economic area of Ukraine or also Russia. I am not sure, if Russia, as the second largest exporter of wood, fails due to sanctions, whether this does not affect the world market.

I am not sure, if Russia, as the second largest exporter of wood, drops out due to sanctions, whether this does not affect the world market.

About 1/10 of the wood comes from there. So what? The world will not end because of that. Nobody denies that it becomes more difficult.

I understand Peter's way of thinking, but for my taste, it is a bit too post-apocalyptic. We will certainly feel the effects. But just because there are supply shortages for parts in the automotive industry doesn't mean that no one can build a single car anymore. It's all a matter of probabilities. How likely is it that a scenario will occur? I consider the scenario in Peter's mind rather unlikely. Other countries also have nice factories.