insulate old garage internally

[pastork]

I'm going to help a friend build a studio in an old uninsulated garage. It will be insulated for year-round use. The idea is at least double drywall on the walls for increased soundproofing. Conditions:

1.5-story old garage in good condition. No moisture, mold, or cracking
plastered brick walls, 30 cm thick
concrete foundation, on top of what I don't know
concrete slabs on steel beams in the ceiling, hard to see but at least 10 cm thick slabs measuring 50x200 cm
the budget is somewhat limiting

How do we frame the walls and what type of insulation? Thickness? Air gap?
The floor is not completely level, a hole 50x50 cm and with protruding edges around. Do you insulate the floor? Frame it as it is and lay plank flooring, level with concrete/screed and frame on top? This is the part I am most clueless about.
How do I frame the ceiling? What type of insulation should I use?
The garage has large, beautiful old doors that will be retained. A new wall with a security door will be built inside.

Grateful for all tips and suggestions out there from knowledgeable people.

 

[norrbottenstorpet]

Is it drained or dry around the feet? You probably need to consider what type of flooring to use, so that it doesn't absorb water and create problems. A floating floor of some kind might be good.

What ambition level do you have for the 'studio'? Stone, brick, and concrete materials might not be what you want to work with as a surface material in a studio, nor gypsum as you mention. Rather, you want heavy sound-insulating materials and asymmetrical proportions (no parallel surfaces).

I would use fairly heavy insulation against the stone wall, possibly with a lighter layer inside (towards the studio room). I would make the framework very sturdy and cross-braced. Inside, just a stretched backdrop fabric.

But I'm not a studio musician or similar, just a music-interested house-builder.

 

[pastork]

Hello, and thank you for your interest and thoughts! I'm not entirely sure where to start with the project.

The idea is to prioritize insulation and x layers of drywall in the walls and ceiling, and also fix the floor in the most suitable way. We'll address the acoustics in the next phase with irregular paneling and screens. If the studio operation moves out, I want the possibility to do something else there.

There's drainage around the foundation. I'm considering chipping away uneven parts, filling the hole with soil/stone, and then adding concrete and leveling compound. Tiles seem good to lay on top, although not at all considering studio operations. So if it might become wooden flooring, maybe it's not worth bringing in a concrete mixer etc., but just using wedges to level the floor. What do you think? What is a floating floor?

What do you mean by heavy insulation? The walls are 30 cm thick. Is 75mm insulation enough? And do I need an air gap between the insulation and the plastered brick wall?

 

[norrbottenstorpet]

hi, and thank you for your interest and thoughts! I don't quite know where to start with the project.

The idea is to prioritize insulation and x layers of plasterboard in the walls and ceiling, and also fix the floor in the most appropriate way. We'll solve the acoustics in the next phase with irregular panels and screens. If the studio operations move out, I want to have the option to do something else there.

Ok, so you're first making a 'normal' room and then building a studio in it. Then I might understand why you'd choose plasterboard, even if I wouldn't have chosen it myself. It's becoming a room within a room then?

There is drainage around the foundation. I'm considering chipping away uneven parts, filling in a pit with soil/rock, and then using concrete and leveling compound. Tiles seem good to lay on top but not at all for studio purposes. If it's going to be wooden floor planks, maybe it's not worth bringing in a concrete machine etc., just use planks to level the floor. What do you think? What is a floating floor?

A floating floor is a floor laid directly on a leveling material, traditionally wooden floors on a bed of dry sand. It's not a bad solution. Nowadays, you might work with other materials than sand if desired.

What do you mean by heavy insulation? The walls are 30 cm thick. Is 75mm insulation enough? Do I need an air gap between the insulation and the plastered brick wall?

Is there any external (inside the bricks) air gap in the wall so that moisture is transported away that way? If not, it might be wise from a moisture perspective to have a certain gap that vents away moisture traveling through the masonry/plastered construction. I'm just a bit afraid it will become a resonant box. I would prefer just to have an elephant mat, or other high-density insulation against the wall. If an air gap is used, it's important that there is sound-insulating material against the air gap, or else you'll have created a good resonant box.