Underfloor heating system, new build solid house

Hello everyone,

we have almost finalized our planning for a new building in 2018. Now we have been reconsidering the heating system quite a bit, as many rumors are circulating.

House: solid construction, 2 floors, no basement, 195 sqm, underfloor heating

Option 1: Geothermal energy: 21,500 euros --> favorite of the builder
Option 2: Gas + solar for hot water + ventilation system: 18,700 euros
Option 3: Gas + solar for hot water / heating
Option 3: Gas/air heat pump hybrid system
Option 4: Air heat pump

[*]Do you have a general recommendation? For us, the total amount after 20 / 25 years would be the deciding factor (investment + maintenance + operation)
[*]Our architect advised against a ventilation system because of maintenance / noise. What is your opinion? Is such a system really necessary? Or is it really advisable to avoid it?
[*]We have often heard that a heat pump with deep drilling does not work properly. Probably if poorly designed?
[*]Do you see it the same way, that a heat pump with deep drilling is difficult to amortize?
[*]Would you consider as an alternative a pure air heat pump or a gas/air heat pump hybrid system?

I would be very happy to hear your thoughts on the topic. Many thanks in advance.

Our ventilation system is located in the attic. If you hold your breath and turn off all background noise, you can hear it on the ground floor (Our side by side refrigerator is louder, but you don’t notice it when watching movies on the sofa). In the bedroom on the upper floor, you hear it a bit louder but still quiet enough to fall asleep normally. For the benefit of fresh air when waking up and coming home, it’s worth it for all of us.

I would also believe that your architect has never been confronted with a ventilation system and is just talking from hearsay. A pity, really. I would always recommend it. Maintenance? What maintenance? Basically, regarding the heating system selection: it has to suit you. You have to be able to rely on the technology.

I would choose option 2 and definitely not build without ventilation.

I would also choose option 2.

In the current property, I have a gas heating system, masonry heater + water jacket, solar thermal.

The ventilation system is unbeatable in terms of comfort. The maintenance effort is to check the filters twice a year and replace them if necessary. Effort about 20 minutes.

From my point of view, I would only take a mix of the variants.