Radiator or underfloor heating: What is recommended under these circumstances?

Hello,

we are about to purchase/build a solid semi-detached house of 142 sqm kfw55 finished by a developer. Standard/included are radiators on the 1st floor + 2nd floor + attic, optionally for 5700 € (plus presumably property transfer tax) underfloor heating only(!) on the ground floor (isso, we don’t need to discuss this in detail). I myself am inexperienced with underfloor heating, I don’t mind it, but I haven’t dreamed about it for decades (unlike a fireplace…) and I am used to radiators and have always managed well with them so far. Please no fundamental discussion about underfloor heating or radiators, medical, swollen feet, dust, “thermal issues”, “should actually” not be more expensive, etc., I’m afraid there’s only arguing here. I want to know your opinion on whether underfloor heating is sensible under these(!) circumstances, i.e. a real approx. 6000 € extra cost, only on the ground floor (so only for the living room, kitchen, hallway, guest WC (and to be controlled separately for these 4 areas)) and in addition (regardless of whether financially and energetically worthwhile or not, it is an old dream) a fireplace in the living room.

What I have read so far, I think:
- In terms of energy consumption it’s not much different, more efficient because of low temperature is fine, but radiators are not that bad in a well-insulated new kfw55 house. I once read something on a specialist trades association’s website about 10% less with underfloor heating in a new building, but since it is only one floor out of three, maybe 5%, that’s max. 50 euros per year.
- My wife so far prefers underfloor heating, but without rational reasons or much experience, simply out of curiosity for something new and presumably better. Like many women, she is often cold even when the room is actually warm, and I could imagine that in such phases she would prefer a “piddling” or clearly heat-radiating radiator over an underfloor heating system that is rather constant and only slowly and slightly “warming up.” On the other hand, the fireplace also helps with that.
- Since we generally prefer it rather cool/use little heating, I even imagine it’s better without underfloor heating in the summer half-year if we want to cool down quickly with a sudden change in weather or conversely warm up the living room within 1-2 hours in a sudden temperature drop.
- Another possible point against underfloor heating: The build quality or coordination of many subcontractors with this developer is not always that great. Radiators, as far as I know (or am I wrong?), are not so sensitive, not much can go wrong there, but I believe a sloppily installed underfloor heating is not so great.
- The only real bigger argument for underfloor heating on the ground floor for me personally so far is the space gained by dispensing with the radiators. We have to take a closer look where they would be and how much they would be in the way, we don’t have the detailed plans yet. In the guest WC and hallway I don’t really care (they would be used very little there anyway), so that leaves the one in the kitchen (I have also often heard that people simply left it out in open kitchens like we have planned). Then only the one in the living room would remain.

I would take underfloor heating without extra cost, but as it is and only to save 1-2 radiators on the ground floor, it does not seem worthwhile for us (under the described circumstances!). Now you come…

Thanks & regards
Jo

1. I would like to point out the following: For most buyers of young used houses, radiators are a deal-breaker. It suggests that saving was done at all costs and that everything else was also reduced to the minimum standard here and there.

2. I myself would never ever take radiators in a new build. They are ugly and old-fashioned and waste the most beautiful space by the window.

3. I don’t know a single person who switched from underfloor heating to radiators.

4. The only disadvantage is the inertia, but it is nowhere near as big as you described. In 1 hour, your room is also warm with underfloor heating (noting that this refers to a gas boiler with a corresponding flow temperature. I have no practical experience with heat pumps).

The extra cost is hefty, but we don’t need to discuss that. It’s just the usual trick with BT.

So 1. Congratulations, you are building a technically old new building. 2. As long as gas is planned, it's okay. For heat pumps, radiators are an absolute no-go for me.

For most buyers of young used houses, radiators are a deal-breaker. It suggests that saving was done at all costs and therefore everything else is reduced to the bare minimum.

As mentioned, underfloor heating is not possible in the upper and attic floors, no matter what I want or like.

To me, this means the opposite: from now on, I will always look at properties with underfloor heating particularly critically; maybe the builder only installed it to distract from other shoddy work... ;-)

I don’t know a single person who switched from underfloor heating to radiators.

But that is not the topic here. And among the new neighbors, there are even more who want to stick with radiators.

The only disadvantage is the inertia, but it is not nearly as big as you described. Your room will be warm with underfloor heating in 1 hour as well.

Ok, I didn’t expect that; I thought underfloor heating would be significantly slower based on everything I have read so far.

(although it should be noted that this refers to a gas boiler with the corresponding flow temperature. I have no practical experience with heat pumps).

The 12 or 17 semi-detached house will have district heating via a central pellet heating system.

The extra cost is hefty, but we don’t need to discuss that. It’s just the usual trick with BT.

Yes, unfortunately. Still, the house/project has its advantages.

If gas is planned, it’s acceptable. With heat pumps, radiators are an absolute no-go for me.

I haven’t quite understood that yet. Both why radiators are tolerable with gas and why not with heat pumps (even though we don’t have one)?

What would bother me much more is the botched job, underfloor heating on the ground floor and radiators elsewhere. How are they supposed to get warm at a flow temperature of about 35° at all.... Why doesn't underfloor heating work on the upper floor?

Since higher flow temperatures in the heat pump greatly reduce efficiency, i.e. consumption increases significantly. And radiators require significantly higher flow temperatures than underfloor heating.

Out of curiosity: what advantages does the project have if the buyer cannot even choose the current state of the art?