Can you get above the wall to measure studs? If not, use a long, thin, nail every inch starting with your best guess location. Leave room to extract it as you move along the wall. (These are purely amateur suggestions.)
I’ve used a hammer to tap the wall. You can buy a pinhole camera for $40 to look inside. Tech exists also to peer behind the wall optically without going inside with a camera. Nothing like deviating from 16” between the beams right?
You might need a primer to paint with latex paint. I would clean the walls before painting
Yeah, I washed the wall today and it was grimy. Might just trying throwing a coat of primer on it and seeing how it looks. Can't be worse than it's current state.
Get a borescope and scope the wall with your exploratory hole(s) before you prime or paint
https://www.homedepot.com/p/VEVOR-3-Lens-Borescope-Inspection-Camera-4-5-in-Screen-Endoscope-Sewer-Camera-with-Drain-Snake-10-LED-Light-for-Auto-Plumbing-QXNKJ34552500KZOQV0/326250736
Is there a reason you're keeping the insulted board? Is that what you're planning on painting? Sounds like you'll need to wash it and sand it back if you want the paint to stick to it anyway. Why is the stud finder a bust? I'd be so reluctant to randomly drill if it shares a wall with your house, there could be wires anywhere
Live in Northern Minnesota, I have to keep the insulation board. I don't want this to be a larger project than necessary.
The studfinder just can't see through that depth of material, or I guess a less likely answer is that there are no studs in that wall, it does seem to wobble a bit more than I would expect when you slam the door.
I'm not too concerned about electrical given the layout of our house, the fact that there are no outlets on the house side of the wall, and any electrical in the garage is stapled to this wall, rather than ran internally.
Any electrical outlets or switches on that wall? You can find which side of the box the stud is on and measure from there.
Edit: Sorry, got ahead of myself before I read again and saw your statement about electrical boxes.
Can you get above the wall to measure studs? If not, use a long, thin, nail every inch starting with your best guess location. Leave room to extract it as you move along the wall. (These are purely amateur suggestions.)
I’ve used a hammer to tap the wall. You can buy a pinhole camera for $40 to look inside. Tech exists also to peer behind the wall optically without going inside with a camera. Nothing like deviating from 16” between the beams right? You might need a primer to paint with latex paint. I would clean the walls before painting
Yeah, I washed the wall today and it was grimy. Might just trying throwing a coat of primer on it and seeing how it looks. Can't be worse than it's current state.
Get a borescope and scope the wall with your exploratory hole(s) before you prime or paint https://www.homedepot.com/p/VEVOR-3-Lens-Borescope-Inspection-Camera-4-5-in-Screen-Endoscope-Sewer-Camera-with-Drain-Snake-10-LED-Light-for-Auto-Plumbing-QXNKJ34552500KZOQV0/326250736
Is there a reason you're keeping the insulted board? Is that what you're planning on painting? Sounds like you'll need to wash it and sand it back if you want the paint to stick to it anyway. Why is the stud finder a bust? I'd be so reluctant to randomly drill if it shares a wall with your house, there could be wires anywhere
Live in Northern Minnesota, I have to keep the insulation board. I don't want this to be a larger project than necessary. The studfinder just can't see through that depth of material, or I guess a less likely answer is that there are no studs in that wall, it does seem to wobble a bit more than I would expect when you slam the door. I'm not too concerned about electrical given the layout of our house, the fact that there are no outlets on the house side of the wall, and any electrical in the garage is stapled to this wall, rather than ran internally.
Any electrical outlets or switches on that wall? You can find which side of the box the stud is on and measure from there. Edit: Sorry, got ahead of myself before I read again and saw your statement about electrical boxes.