[nemo44x]

They’re much more efficient (and comfortable imo) than other systems. You’ll see pretty big costs savings. But yes, you need to be in a climate that sees long, cold winters to get the best of them I guess. Or if your home has lots of tile/stone/concrete flooring.

You’re right though, they take awhile to heat up and if you’re in a place where you may need heat at night and AC in the day, they won’t be ideal.

[2rsf]

Pretty big costs savings compared to what? if you compare radiators to floor heating, both connected to the same heat pump system than the savings are not significant

[nemo44x]

It's because of efficiency. The entire floor becomes a radiant source - this is a massive thermal source. A heat-pump is only part of the equation. You need to deliver the heat still. A radiator is generally a bad way to deliver heat from a heat pump. Radiated floors are much better. About 40% more efficient than radiators from the same heat pump.

Not to mention radiators are sort of lousy ways to heat a room anyways. They take up space and leave one side too hot and the other too cold.