Sound and heat proofing garden studio

[Berry Newbie]

Hi everyone,
Newbie here. Building a studio in the garden and wondered about insulation. Aside from heat insulation, I basically want to soundproof it as much as I can.
It would be helpful if anyone could comment on how the following soundproof approach would work for heat insulation and where sound and heat overlap. This is a lay out of all the wall layers so far, from outside in:
- shingles for esthetic look
- ⁠chip board
- ⁠wooden frame work to serve as wall, using 2x4 studs, and filled with 100mm fiberglass
- ⁠Polyethylene sheet serving as vapor barrier
- ⁠2 layers of 5/8 plasterboard (recommended density for sound insulation) with GreenGlue in between.

Then a builder friend of mine says ‘fiber glass is dung, damp and animals love it’ and wondered if people share his view?
He recommends Steico sheathing board, saying it insulates for both heat and sound, does anyone have any experience with that material?

Lastly, screwing sound insulation material to wooden studs apparently transmits sound via the screws thus negating the insulation. Sounds a bit dramatic maybe, or is that in actuality a real risk?
Soz I know it’s a lot, would love some help on this.
Thanks everyone,
Newbie out

 

[Cabinetman]

Second layer in, chipboard? Or do you mean OSB? I will let more knowledgeable people tell you about insulation.
Fibreglass- loft type insulation is ok unless it gets wet! Then it’s useless.
Ian

 

[Molynoox]

Air gaps are the main issue for sound in my experience.

Watch gosforth handyman YouTube on the topic

 

[Jameshow]

Also offset your battens to the midpoint between studs that way noise isn't transmitted via the stud walls as much.

 

[Fitzroy]

Fibreglass insulation is considered poor for sound insulation, it also tends to slump in cavities overtime so not great for thermal either. Rockwool batts are a better option.