Is there OSB behind the drywall, perhaps?

[HerrOklar]

Suspect that the carpenters "forgot" to put OSB on a wall behind the drywall. It doesn't sound "solid" enough when I knock. Does anyone have a home remedy for checking this without damaging the wallpaper and drywall?

 

[jan_martinsson]

If there is a contact/light switch or something similar, you can just open it and take a look, right? Otherwise, you might have to drill a small hole under a molding or something like that.

 

[Alfredo]

Check by the wall socket or switch is probably, as mentioned, the easiest. If for some reason this doesn't work, try inserting a pin in some hidden spot. The hole will be microscopic and likely won't be visible.

 

[HerrOklar]

I did the pin trick and I feel convinced that there's OSB back there because it came to a complete stop after about 12 mm.

THANKS

 

[Hubbe2]

you might have hit a stud, I would have loosened an electrical box and checked, or inserted the needle in another place as well.
No paintings or anything to hang on the wall? Then you can clearly see if there's something behind.