Steel rebar/sleepers behind concrete wall?

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JackJ

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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!
 
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
 
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.
 
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.

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
 
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?
 
drill into the mortar joints - if you hit steel, move or go fish ! :rofl:
 
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
 
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?
 
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
 
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.
 
neal, no matter what size, it MAY be able to bust thru light wire mesh,,, if you're trying to hammer drill thru rebar, dick & i wanna be the guys selling you carbide bits :clap: willing to bet its the same in canada, too !
 
neal, no matter what size, it MAY be able to bust thru light wire mesh,,, if you're trying to hammer drill thru rebar, dick & i wanna be the guys selling you carbide bits :clap: willing to bet its the same in canada, too !
You are sure right about that. My hammer drill is a 1 and 1/2 drill and every time you hit steal theres a good chance you lose another tip off the drill bit. Thats why i always start with a small bit. I would rather lose a $40.00 bit then a $140.00 bit. Later Paul
 
What I ment was, with a regular drill with a carbide bit will drill steel but could overheat in concrete witch melts the silver solder. I suspect that is what has happened.
 
Thanks for all the feedback guys. I bought a cheap HF 1/4" hammer drill, as this was the heaviest work I'd be doing, and it's only for a few holes. But the instructions and the picture on the side of the drill differ as to which way one pushes the switch to make it a hammer drill! I called HF, who said that the manuals are often done overseas with poor quality control. So I went with the picture on the drill, but not sure if I was right. HD guy said I could tell which it was by the sound, not even drilling just running it, but I couldn't tell. Fortunately, I picked a new location that worked, and used that level for all holes. I think I have the right setting for the hammer drill function; don't want to switch it to compare and ruin a bit, though. Thanks again.
 
Thanks for all the feedback guys. I bought a cheap HF 1/4" hammer drill, as this was the heaviest work I'd be doing, and it's only for a few holes. But the instructions and the picture on the side of the drill differ as to which way one pushes the switch to make it a hammer drill! I called HF, who said that the manuals are often done overseas with poor quality control. So I went with the picture on the drill, but not sure if I was right. HD guy said I could tell which it was by the sound, not even drilling just running it, but I couldn't tell. Fortunately, I picked a new location that worked, and used that level for all holes. I think I have the right setting for the hammer drill function; don't want to switch it to compare and ruin a bit, though. Thanks again.

You can't tell by just running it you have to have the bit in the drill and push down on something like a piece of 2x4, one way it will hammer and drill, the other way it will just drill. Later Paul
 
Thanks; I'll try it on some wood. That's odd that the guy at HD was wrong? :)
 
jack, you're embarrassing yourself & some of us, too,,, IF you EVER want to move on up off the 'junior member' status, remember this ONE basic dictum of home ownership - ' THERE IS NO SUCH THING AS A GOOD CHEAP TOOL ! ',,, this is often follow'd by #2 - ' I NEED TO GET ( buy ) THE RIGHT TOOL TO DO THAT, HONEY ! ' this is how the almighty intended us men to collect tools.

NEVER listen to anyone wearing orange aprons or red vests even if they're got grey hair UNLESS they're young, attractive, nice smile, & have big tits.

ps - conc bits don't work well on wood ( #3 - use the right tool for each task ! )
 
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Sorrey Paul sometimes I don't get updates for hours.
I've had the same 5/8 dill bit for 10 years, hundreds of holes in concrete. when hitting rebar add water to cool the bit and when it slides sideways lots of work to get the bit out and the shank is well worn. The only diff between conc. bit and twist drill with carbide is how it is sharpened. You can be sure that Jack tried drilling the hole with a 49 cent bit in a reg high speed drill it worked good untill he hit the real conc. inside
and melted the bit.
 
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