I would like to securely attach window security bars to the outside of my new house but it appears to have this fake facade. Its a row home (e.g. townhouse) in Baltimore City and the front is brick (which I understand how to to work with) but based on the edges around a pipe coming through the back exterior, it appears to be a 1/4" metal mesh with stucco over it.
I drill through the area in the top right of the image and it quickly goes through the first layer, then drops to the second layer, and quickly goes through that. I can't find anything solid within 2.5 inches. I tried using a magnetic stud finder and that did work either.
The best think I can think of is use some of those heavy duty drywall anchors. Any other suggestions?