Building according to the Energy Saving Ordinance 2016 or KfW55

Hello,
I have been following for a few weeks and have an important question before awarding the contract.

I am building a turnkey city villa (catalog house) with an air-water heat pump, living area approx. 118 sqm, the planning contract has been awarded. The general contractor offers standard according to the Energy Saving Ordinance 2016 and increases the price for execution in KfW55 by approx. 13,000.00 euros for improved insulation under the floor slab and ceiling above the upper floor and replacement of bricks from Poroton T12 to Poroton T9.

The subsidy for KFW55 is 18,000.00 euros, the subsidy for KfW55 EE is max. 26,250.00 euros.

If I build in KFW 55, I calculate additional costs of 13,000.00 euros for improved insulation, 2,000 euros for the energy consultant and 10,000.00 euros for a decentralized ventilation system. This uses up my subsidy. On the other hand, according to my research, there is only a minimal saving of approx. 100.00 euros/year with KfW55 compared to the Energy Saving Ordinance 2016 on electricity for the air-water heat pump.

Of course, the higher price expected in the event of a possible sale speaks for KfW55, but I do not intend to sell.

Otherwise, the savings compared to the Energy Saving Ordinance 2016 to KfW55 are only marginal. In addition, the additional ventilation incurs maintenance costs.
With KfW55, the house is sealed so tightly that fresh air must be supplied again through fans. You pay for the increased insulation and then for the ventilation needed to compensate. Houses according to the Energy Saving Ordinance 2016 are not so tight and do not require ventilation.

I am putting the topic up for discussion.

I am curious about the various opinions.

Regards
Raiweired

Houses built according to the Energy Saving Ordinance are just as airtight as kfw 55 and require ventilation. Whether it is window rebate, decentralized, central controlled residential ventilation, or someone who regularly opens the windows.

Otherwise, the savings compared to the 2016 Energy Saving Ordinance to KfW55 are only marginal.
[QUOTE="Raiweired, post: 504726, member: 55514"]
Houses built according to the 2016 Energy Saving Ordinance are not so airtight and do not require ventilation.

[/QUOTE]
Do you have to install a controlled residential ventilation system for KfW55?
The house is just as airtight as an Energy Saving Ordinance house. You won’t notice the difference. If you don’t ventilate in an Energy Saving Ordinance house, a) you can also risk mold and b) it will always smell like a puma cage.

Sure, the higher price that can be expected in case of a possible sale speaks in favor of KfW55, but I don't intend to do that.

No, but you want to live there longer and participate as little as possible in further rising electricity costs. Therefore, a low electricity consumption (= heating costs) should also be a goal.

Additional ventilation even causes maintenance costs.

Which ones? Go to a filter store and buy suitable filters for the systems (also gladly to cut yourself). That reduces maintenance to €10 per year and some effort.
But what I find much more important and you don’t even mention is the INCREASED comfort, which you can’t express in €. That should be the main focus.

Thank you very much for the answers

Energy Saving Ordinance and KfW55 are therefore equally airtight. So the additional insulation and the switch to T9 provide more insulation and thus less electricity consumption for the air-water heat pump?

Whether I have to install controlled residential ventilation with KfW55 is not yet decided. I approved the draft for the house today and according to the general contractor, the energy consultant is supposed to check next week whether controlled residential ventilation is necessary.

Maybe there is also a better insulated roof with KfW 55 ... That could also be good as heat protection.

Yes, the additional costs amounting to 13,000.00 euros for KfW55 include improved insulation under the floor slab and ceiling above the upper floor, as well as the replacement of bricks from Poroton T12 to Poroton T9. The ceiling above the upper floor will be constructed as a filigree slab.