Kfw70 with poroton and utility water WP + gas + decentralized ventilation

hello expert, builders and friends of energy efficiency,

as a new builder (Stuttgart region) I have been strongly focused on the topic of "energy" for a few days now.

Fixed from the latest calculations with architect and structural engineer is a plastered Poroton T8 - solid wall (Poroton T8). according to the Schlagmann Poroton table, this variant with 36.5 bricks meets the KfW 70 requirements.

Triple glazing is also fixed. The house has 220 sqm of area.

The goal now is to create an optimum for the house energy to generate KfW 70 without unnecessary loss of money. After the latest energy fair here in the region and initial consultations with building technology providers, I have this house energy design as optimum:

1) domestic hot water heat pump, also with photovoltaic support, as I will have photovoltaic with self-consumption (approx. 5 kWp from the roof according to plan)
2) a gas boiler for underfloor heating and peak load in winter
3) decentralized ventilation system with energy recovery

Is such a combination sufficient for the KfW 70 goals?
If not, where would the weak point in the constellation be?
Thanks in advance for any answer or recommendation.

p.s. I have removed solar thermal from the plan, because the amortization calculation with photovoltaic and self-consumption is much more attractive in my case

Just as additional information: The property is already prepared with a gas connection, so the topic of gas is an advantage for me......

And what is the domestic hot water heat pump supposed to be good for if you also have a gas boiler?

What nonsense. You want a heat pump for the water and the gas boiler for heating? What kind of heat pump do you want to install? A ground-source heat pump for nearly 20k? Plus the gas connection? Go to a proper energy consultant. If gas is available on the property, depending on the length of the internal development, you'll still pay your 2.5 to 5k euros for the connection. A heat pump also costs money, you need a lot of technology, separate boilers, etc. Is it worth it?

Hello,

....Is such a combination sufficient for the Kfw 70 targets?

Who should be able to answer that, since the values for the reference building are unknown?

...if not, where would the weak point in the constellation be?

The basic concept, because it’s half-baked!
How one intends to catch up with the qp´´ bonus of the reference building with gas condensing is strange to me!
If photovoltaic, then in combination with a heat pump for heating and hot water! This way, the self-consumption shares can be appropriately increased. Cooling might be necessary in summer. With gas, you can cook and heat, but with a heat pump in combination with photovoltaic, you can often heat, cool, and cook for free! ;-) Which type of heat pump would be effective can only be known after the basic assessment, where the actual demand (power, energy) for heating and hot water is determined.
Tendentially, an air heat pump for mild locations, rather a brine heat pump for cold ones. The latter does not necessarily require an expensive deep drilling. Often, for example, a trench collector is sufficient, where you can contribute a lot of your own work.

Best regards.

Hello wastl,

it’s not nonsense, because this combo comes exactly from an energy consultant. And there are also the so-called ". BrauchwasserWP ". The price: not even 4K.
take a close look "brauchwasserWP", no brine, no air-to-air. No probe.

of course, I can slowly start to share the first concrete data now, but such a concept was presented to me by an energy consultant.

Since I was previously leaning towards split heat pumps, this combo has driven me crazy.... that’s the reason for my thread here.