Price difference new construction, KfW 70, KfW 55

Good evening dear forum,

I am looking for an approximate guideline on how much the additional costs are from a normal new build to KfW 70 and KfW 55. The low interest rates are very appealing, but is the extra cost for a KfW house worth it? Or should one perhaps only implement parts of a KfW standard?
A fireplace and a reasonable gas boiler might be sufficient, after all.

Thanks for your help!

Best regards
Nils

Hi Nils,

The question is difficult to answer, it depends on so many factors. Above all on what you want to build anyway. Many prefabricated houses already seem to compete in the KFW 55 league, or if you want to equip a solid house with a heat pump and ventilation anyway, it may well be that the additional cost from 70 down to 55 is quite low.

Tuning a house designed in the "basic equipment" for KfW 70 to KFW 55 will be more expensive than the interest savings it brings you.

Values from €5000-15000 were circulating here in the forum, with still significant outliers upwards.

Others can say more about the current legal situation here, but so far it seems that the expert required for KFW 55 alone eats up your interest savings.

You can forget about heating cost savings in such considerations anyway. A modern house has heating costs on the order of €40-80 per month. If you save 20% of that, it won’t get you anywhere...

Long story short, financially it will almost certainly not be worth it, unless you plan to build a house that barely misses the KFW 55 standard and can be brought above the KFW 55 threshold with little effort.

Due to the now applicable new level of the eco-madness regulation, a gas boiler will only work with a relatively large solar system. There is no big savings in acquisition compared to an air-water heat pump. Only in operating costs are you of course better off with the gas condensing boiler.

Many greetings,

Andreas

Others may be able to say more about the current legal situation here, but so far it has apparently been the case that the expert required for KFW 55 alone eats up your interest savings.

I would like to bring my question back into focus:

Thank you for your response. How expensive would the required components be approximately compared to the normal standard? How does it compare with solid houses versus prefab houses? Many offers advertise with an all-in package. Regards Nils

Hello Nils,

I am looking for an approximate guideline on how much the additional costs are from a normal new build to KfW 70 and KfW 55. The low interest rates are very tempting, but is the extra cost for a KfW house worth it? Or should one possibly only implement parts of a KfW standard?

That cannot be answered in general terms, because it depends ....

How large is the single-family house, with/without basement, which technology – especially controlled residential ventilation with heat recovery – is installed, what kind of wall construction?

A fireplace and a decent gas boiler might do as well.

For those providers who already offered KfW 70 as standard last year, not much will change, since they probably work with an air-to-water heat pump; this means they comply with the requirements of the Energy Saving Ordinance 2016 without additional effort. This is due to the (positive) change in the primary energy factor for an air-to-water heat pump. Therefore, the step to KfW 55 is manageable.

If you want to build with a gas condensing boiler, it looks different; you have higher effort to meet the requirements of the Energy Saving Ordinance. More insulation and at least a solar system for domestic hot water heating. The monetary effort to comply with the Energy Saving Ordinance 2016 – compared to an air-to-water heat pump – is higher.

A fireplace is solely for comfort; wood costs a lot of money and only pays off if you get wood cheaply or for free. Apart from the fact that in modern single-family houses even the 4 candles of the Advent wreath provide plenty of warmth.

So, you need to provide more specific information in order to answer your question somewhat reliably.

Rhenish regards

Quick question, is it actually possible to achieve the Energy Saving Ordinance 2014 with a gas condensing boiler and a controlled residential ventilation system without relying on solar?