ᐅ How to Design an Efficient Heating System for a New Building?

Hello homebuilding friends,

We are currently in the detailed planning phase of our house and need some quick support. The final goal is to build a KFW40 energy standard house.
I have tried to research extensively online but still haven't figured it out.

How exactly should a heating system be designed to be as efficient as possible? Like many new builds, we are planning a heat pump with underfloor heating. I have read that room thermostats should be omitted so the system can self-regulate. I have also read that a buffer tank is a bad idea.

I have read that the heat pump should operate at low temperatures to remain efficient. Additionally, I have read that a separate heat pump should be used for domestic hot water production. However, I have also come across many conflicting opinions.

Our heating technician wants to install a buffer tank with an electric heating element.
Right now, we are quite confused.

Could you help clear up the fog for me? What should an optimally designed heating system look like?
Thanks and best regards from a beginner builder

1. Correct calculation of the heating load according to your requirements. For example, with a maximum supply temperature of 30°C (86°F) and your desired indoor temperature.
2. No buffer tank.
3. Exemption from ERR.
4. The heat pump also provides domestic hot water. Having two separate units is unnecessary (like having one car for commuting and another for shopping).

The electric heating element in the heat pump is a backup in case the heat pump cannot reach the required temperatures during the coldest winter periods. An additional heating element is unnecessary.

nordanney schrieb:

1. Correct calculation of the heating load according to YOUR requirements. For example, with a maximum supply temperature of 30°C (86°F) and your desired indoor temperature.
2. No buffer tank.
3. Get exemption from ERR.
4. The heat pump also provides domestic hot water. Two separate units are unnecessary (like having one car for commuting and another car for shopping).

The electric heater in the heat pump serves as a backup in case the heat pump cannot reach the required temperatures during the coldest winter periods. An additional electric heater is not needed.

Thank you very much in advance. Does that mean a heat pump can have two outlets? Is a domestic hot water tank (fresh water storage tank) necessary?

So the electric heater is integrated directly into the heat pump?

Tzubaka schrieb:

Thank you in advance. Does that mean a heat pump can have two outlets? Is a fresh water storage tank necessary?

Is the heating element integrated directly into the heat pump?

No. A 3-way valve is installed for this purpose. This allows the domestic hot water tank to be heated instead of the heating water.

And yes, you will need some type of storage tank for potable water. There are different options available. The size depends on your specific demand.

nordanney schrieb:

No. A 3-way valve is installed there. This allows the hot water tank to be heated instead of the heating water.

And yes, you will need some kind of storage for potable water. There are different options available. The size depends on your household’s demand.

What kind of options are there? And what is the usual calculation per person?

Unfortunately, I couldn’t edit it further. I’m still not completely sure about the heat pump. How exactly is the water heated to, for example, 60°C (140°F)? Does this happen in the hot water tank using electricity? Because the heat pump operates at around 30°C (86°F). Or am I misunderstanding something?