KFW70 or KFW55 experiences?

Hello dear home builders,

I am sure this topic has already been discussed several times here. However, I did not find any entry so ad hoc and therefore I am asking my questions very specifically. We are currently looking around the market regarding house construction.

It seems that four providers have emerged with whom we could imagine building a house.

Now the question is whether we want/should build a Kfw70 or a Kfw55 house.

Which one should we go with? Also considering the upcoming Energy Saving Ordinance 2012... Does anyone already know what it will look like?

Is the additional cost worthwhile in connection with the savings in energy?

One house builder, Hanlo Häuser, basically builds KFW70 houses and says that is sufficient. According to him, the additional costs are not covered by the savings one has. The walls at Hanlo have a U-value of 0.13, which is quite good. However, the standard is only double-glazed windows. The standard heating system is an air heat pump.

Otherwise, Hanse Haus, Fingerhaus, and Bien-Zenker are still in the running. U-values are very similar there, as is heating. As for the windows, however, they build with triple glazing. Is double glazing really enough?

Unfortunately, we are very unsure about this and it would be great if you could give us some tips.

Thanks and regards

daugstin

Hello,

...What should one go with? Also considering the upcoming Energy Saving Ordinance 2012... Does anyone already know what it will look like? Are the additional costs worthwhile in connection with the energy savings?

It is undoubtedly certain that energy prices (all energy sources) will rise significantly in the future. Looking back, one can see that annual price increases were sometimes significantly above the general inflation rate. This will certainly continue to be the case because energy for heating and hot water preparation is indispensable.
One slogan says: "The best energy is the energy that is not consumed or needed in the first place."
KfW standards always mean higher investments compared to the respective current Energy Saving Ordinance requirements. However, this is primarily from a primary energy perspective! This does not automatically mean economic feasibility for the builder.
In addition, it is not uncommon for Energy Saving Ordinance or KfW certificates to have been "beautified" and for the expectations of the builders regarding the final energy consumption often not to have been met in reality. Mostly due to insufficient efficiency of the building technology. Frequently, even the primary energy requirements of the certificate are not met.
The new Energy Saving Ordinance requirements will again significantly drive investments upwards!

...One house builder, Hanlo Häuser, generally builds KFW70 houses and says that is sufficient. According to him, the additional costs do not match the savings one has.

Every GU/ GÜ (general contractor/general project manager) or BT (property developer) has its own sales and calculation concept. Naturally, the argumentation towards prospective buyers is subordinated to this. For example: If 80% of customers, for whatever reasons, request a KfW 70 or Energy Saving Ordinance house, the sales strategy is aligned accordingly. Those deviating from this preset direction as prospects usually have poor financial odds.

...The walls at Hanlo have a U-value of 0.13, which is quite good. The standard windows are only double-glazed.
The standard heating is an air heat pump.

The U-value of individual components is certainly important, but overall, for an economic assessment, the total final energy balance is decisive. With heat generators, combo or compact units are often ordered cheaply and installed in large quantities on the market, although these often operate significantly less efficiently in practice compared to a modular setup.

...We are unfortunately very unsure about this and it would be great if you could give us a few tips.

Consultation and review of the planned building technology by a sales-independent expert before a contract is signed!
Best regards

According to the planned Energy Saving Ordinance 2012, one can already forget today's KfW70, as well as double glazing. Air heat pumps only make sense with efficient building envelopes. So between KfW55 and 3-liter house.

You might want to involve other developers as well. As far as I know, the current KfW70 will soon become the Energy Saving Ordinance 2012 standard. You should make sure that the energy balance is not only beautified but effective and verifiable. For us, the desire for KfW70, for example, led to having both inter-rafter and under-rafter insulation in the roof. Triple-glazed windows are included anyway with [DEURA].

....Air heat pumps only make sense with efficient building envelopes. So between KfW55 and 3-liter houses.

Air heat pumps do not necessarily require a particularly efficient building envelope. The decisive factors are the size of the heating surfaces and the heating medium temperatures in relation to the room heating loads.

Regards

@€uro

well, then install an air heat pump with its annual performance factor in old buildings with inefficient building envelopes and later explain the point when the meter spins.