Soundproof but not heat? Between joists

[krumbukt]

I want to reduce noise from the upstairs to downstairs, and vice versa. But on the ground floor, I have a stove, and I would prefer that as much heat as possible from the ground floor seeps up to the upper floor. What kind of insulation would fit then? Plasterboard? Not mineral wool? Help.

 

[Byggareberg]

I want to reduce noise from upstairs downwards, and vice versa. But downstairs I have a fireplace, and I would prefer that as much heat as possible from downstairs seeps up to the upstairs. What kind of insulation is suitable then? Gypsum? Not mineral wool? Help.

In our house, the ceiling is lowered by about 30 cm downstairs. Just having the air in between dampens the noise incredibly much. However, larger noise impacts remain, such as people walking on their heels.

 

[Gabbe1]

Wood shavings in intermediate floors dampen sound better than mineral wool, at the same time they are worse at insulating heat.

 

[jawen]

I want to reduce noise from the upper floor to the lower floor, and vice versa. But on the lower floor, I have a fireplace, and I would prefer that as much heat as possible from the lower floor seeps up to the upper floor. What kind of insulation is suitable? Gypsum? Not mineral wool? Help.

Are you trying to reduce structural noise or voices, i.e. sounds from people, TVs, and the like?
Structural noise (when people walk, run, thump on the floor) is transmitted through the floor into the walls & other connected structures.

Rooms also function like a speaker, where resonances amplify the sound.
If it's structural noise that bothers you, you should consider some form of "floating floor" over the old floor on the upper floor, so vibrations are prevented from spreading to the structure.
Stepisol is such a product, & you can lay parquet flooring or similar right over it BUT the parquet floor must not touch the walls!

https://et.se/wp-content/uploads/2022/05/Broschyr-Stepisol-2022-4.pdf

If it's voices, TV, etc., that disturb you, you must first investigate how much of the noise comes from the staircase and the opening between the floors.

Stylish sound absorbers on the walls in the staircase prevent sound from reflecting (bouncing), down to the lower floor.
Air leaks between the floors spread voice/TV noise tremendously, and the only thing to do about this problem is to seal them.

And your fireplace will still heat the upper floor (even if the system becomes a bit slower), as the entire floor structure heats up & emits heat like a large "radiator" over the entire floor area of the upper floor.