ᐅ Heated surfaces in rooms with significantly increased heating demand

Since an extension is being built onto my existing property, there are unfortunately some issues with the heating load in this new area.
(Underfloor heating will be installed throughout the entire heated space.)

Because this room (living room) mainly consists of exterior walls, it has a heating load of 54.37 W/m² (1909 W).
In the rest of the ground floor, we have about 25 W/m².

Is there a way to heat this room in the extension (living room) without having to increase the heat pump’s supply temperature to nearly 40°C (104°F)?

Unfortunately, the heating surface is limited to the floor and cannot be increased.
Would using larger pipe diameters and increasing the flow rate help in this case (if that is even possible)?

Why can’t the area be increased?
Ceiling, walls, etc.?

Otherwise, it will be tight and there will be many circles.

The only option would be a wall heating system on the interior wall facing the dining room/kitchen.
The ceiling will be an acoustic ceiling, so a ceiling heating system is not possible.

Hmm, a 20°C (68°F) design temperature isn’t exactly generous. Have you already considered the flooring and so on?

20°C (68°F) is more than sufficient...

Yes, there will be hardwood flooring in this room

LostWolf schrieb:

Is there a way to heat the room in the extension (living room) without having to raise the heat pump’s supply temperature to nearly 40°C (104°F)?

I don’t fully understand the issue. This is my extension (designed for 22°C (72°F)).

My extension is smaller but has nearly the same heating load per square meter. I installed the underfloor heating with a 5cm (2 inches) spacing. Result: supply temperature around 30°C (86°F) for 21.5°C (71°F) indoor temperature this winter.