I recently moved into a home that was built in 1989...We are wanting to mount a TV above the mantel but have some questions as to the construction of the fireplace. The fireplace is 1-1.5 inch stone from floor to ceiling, I went ahead and drilled a small pilot hole to see what I was dealing with behind the stone. To a bit of my surprise I went through the stone and cement backer then hollow space (code Im guessing). I was able to stick a rod through the pilot hole to a depth of about 5.5 inches before hitting what Im guessing is the internal portion of the chimney itself. My first thought was if the stone and backer would be enough strength to hold the mount and tv (65" TV and soundbar) at less than 100lbs total. Im certainly open to drilling further in if I had to but wanted to get some guidance on this before moving forward. Im hoping someone can give me some guidance on where to go from there.
TIA
TIA