Exterior wall construction

[Xasa]

My "simple" project hit a snag. Trying to mount a shower rod. While the wall sounded solid, I hit air on the lower holes and something too solid to drill on the upper holes. Discovered the existing screw in the door track isn't going into anything. Anyone have experience with mods that might know what's going on in the wall? Esteem 27U
(pic came in rotated 90 degrees left)

[dxrobertson]

Originally Posted by Xasa

Discovered the existing screw in the door track isn't going into anything.

This is common. My shower head mount is screwed into "nothing", dangling ready to fall off the wall.

The "nothing" walls are a very thin wood board with the veneer/wall paper glued to it, wall being I believe 1/4 inch thick. You can mount to this empty space wall with anchors for light weight applications.

I believe that some of the framing in these units is aluminium and thus the encounter of solid material. Not sure what framing is aluminium and what is/may be wood; but suspect the framing along the outer shell to be all aluminum.