JackJ

I'm "simply" (or so I thought) trying to drill holes in my garage wall to put up v-hangers and shelving, but there's some type of metal behind it. Where I first drilled turned out to be just about 1/4-1/2" of concrete before I hit the metal. My stud finder isn't picking it up, even at the hole. Unless it's a solid piece of metal behind it the entire wall? I'm in FL, if that helps understand the construction.
So, any thoughts on what I'm looking at back there, and how I should go about accomplishing my "simple" job? If it's a sheet back there, can/should I go into it? Already ruined one masonry bit trying to, not even realizing I was hitting metal. Do I simply need a better stud finder?
Thanks much!

mudmixer

Are you sure your garage is built with wood studs? Many home in Florida are built using concrete block, but rebar would be located at least 1 -1/4" from the surface unless you were drilling into a cast-in-place section (tie beam, bond beam) with misplaced rebar.

You may need a different drill and bits if it is not wood.

Dick

JackJ

No, I'm not at all sure that it is/isn't wood. To clarify, I'm drilling from the inside, and it's about 1/4" in that I hit some type of metal. That's the extent that I KNOW. What I've read/heard is that there may be rebar in there as reinforcement, and also that there could be steel sleepers, which I don't fully understand. That's the extent of my knowledge (which ain't much!)
I'm tempted to chip away around the hole to get a better view of what I'm dealing with, but obviously would rather not if possible.

paul52446m

You could have re rod going vertical in the cores of the block. Are you drilling
into the mortar joint between the blocks? Some block walls have a continues
steel that goes horizontal between the blocks. Paul

JackJ

The blocks are 15.5" across by 8" high, and my first hole was 5.5" in from the left and 3" down, so it doesn't seem like I would have it any, except possibly the horizontal one if it's through the core. Would it just be one per block, and how wide would it be?

itsreallyconc

drill into the mortar joints - if you hit steel, move or go fish !

mudmixer

Jack -

Since you know the approximate dimensions of a concrete block, you probably have a block wall.

You may have a wall made of concrete block (typically 15 5/8' x 7 5/8" face dimensions) and you may have drilled into a horizontal mortar joint where there could be steel (wire) joint reinforcement (not typical rebar) that is usually spaced every 8", 16" or 24" on center vertically. Joint reinforcement embedded in mortar can be tough on drill bits/ drilling.

The reinforcement is run horizontally, so try 8" above (7 5/8" plus 3/8" mortar) to find another mortar joint level. This reinforcement is not put in the cores of the block and is intended to be in the mortar joint and is relatively close to the surface of the wall.

Dick

JackJ

Thanks for the detailed explanation! How wide/big of a diameter would this steel wire be? I should be able to simply go up/down 2-3" and be fine, right?
Although I am still a bit puzzled, as you say that it's put into the mortar joint, yet this was 3" down from the horizontal mortar joint. The one visible on the surface is what we're talking about, right?
Also, I don't understand that it runs horizontally and is spaced every 8", 16" or 24" on center vertically. Is that an additional vertical wire? And is it centered in the block, or also in the vertical joints?

mudmixer

Joint reinforcement is always wire and can vary in gauge, but is well under the mortar joint thickness.

Based on your description and dimensions, it is just a guess based on normal construction. Vertical reinforcement (deformed steel bars ranging from 1/2" or more in diameter) in the core of the block, which is a minimum of 1 1/4" from the face of an 8" block.

I suggest you try another location and drill or bit after you understand what kind of wall you are attaching something to, since that is necessary to determine if the wall will support the loads you think you have.

Dick

nealtw

carbide concrete drill bit will drill thru steel. I suspect the you were not using a hammer drill while you tried this. go rent a drill and try it again.