Experiences Single-Family House KfW55 - Assigning Tradesmen Yourself?

For "us," the year of construction counts and thus the energy consumption in the year of a house, not the Energy Saving Ordinance.
Ask someone who wants to buy a house about the Energy Saving Ordinance – you will then see the question marks above their heads.
It does not matter whether the house costs €900 or €1200 per year in energy, but it is important that it does not cost €2500.

If a simple panorama window from the 50s were not so drafty, one would tolerate that through this one window €309 per winter month is wasted. The new replacement is otherwise too expensive... there is a lot of tolerance regarding heating values. More important are the location, the layout, and the equipment. That shapes the value for "us."

Basically, among those who deal with the Energy Saving Ordinance, the opinion prevails that too much of this Energy Saving Ordinance could rather harm the house (mold).
Who are "one" and "us"? Colleagues, neighbors, acquaintances, friends from every class and every age.

We ourselves installed KfW 70 instead of the required KfW 100. We wanted controlled residential ventilation anyway; more would not have been worth it to us.
If we earned money more easily and had more equity: I do not think we would have invested more in insulation, technology, and so on.

Regards, Yvonne

Great for the feeling, less so economically.

Good for the regulars' table, possibly wrong in individual cases. For us, the additional costs were €6300 + €2500 for the expert, so just over €8800.

With the €5000 from §153 and the €1250 from the construction supervision program, €2700 remain. However, the interest on the €100,000 was also 0.7% cheaper than for the rest with us. Over the term, we pay at least €2700 less in interest, depending on special repayments rather €5-7k.

It is and remains a case-by-case decision. This pub talk also annoys me. But that seems to be very common when it comes to the topic of [Haus]. Lobbying is being done against all sorts of things.

For us, the leap to [KFW55] also made sense. A ventilation system was mandatory for us for reasons of comfort, and the last thing missing to reach [KFW55] was a minimally better insulation of the top floor ceiling for just under €1,000 (+ expert €600)... In addition, there was a €5,000 repayment grant, a slight advantage from a cheaper loan, and a valuable house due to slightly better insulation.

However, [KFW40] was completely uneconomical (for us).

: Where do you know that KfW40 would not have been economical? Did you also have KfW40 calculated? Or were the additional costs only roughly estimated?

We had 2 variants calculated for how to achieve KfW 40 and knew the additional costs. The subsidy plus heating cost savings would not have paid off over 100 years... Additional interest is not even included yet...

Of course, I have to say that we have geothermal heating, and thus naturally very low heating costs (investment ignored), which makes any additional insulation practically uneconomical.

If there had been another comfort advantage, such as with a controlled residential ventilation system, we would have done it, but that advantage does not exist from KfW 55 to KfW 40.

I also have a Kfw70 house (or now Energy Saving Ordinance) and a ground-source heat pump, which results in about 350 euros heating costs per year/30 euros per month. The saving potential is therefore low. With other heating technology, it is somewhat higher.