Concrete anchor size recommendation

[nolanpro]

I need to install a few concrete sleeve anchors in my ceiling. I live on the 3rd floor of a 7 story building built around 1907 (after the San Francisco 1906 earthquake).

I was wondering how thick the floors are likely to be. The last thing I want to do is poke a hole in my upstairs neighbor’s floor with a hammer drill. So what’s a “safe” gauge and length?

I’ll be hoisting my heavy mountain bike, so I’m thinking 2 or 3 sleeve anchors. The load will be straight down from the ceiling, so its a dynamic tension load.

Is 1907 concrete as strong as today’s or will it crumble when I attack it with a hammer drill? I do see several existing anchors around the house to hold up sprinkler pipe.

I’m a concrete noob, thanks for any help!

[RTF]

The concrete is apt to be quite hard and brittle. The way to gauge the depth is to look for existing penetrations where you might be able to insert a stick rule or tape measure. My guess ie 4" to 6", but that's a guess. Since you see anchors in the ceiling slab you know they'll work. You can try a 3 - 3.5 " depth anchor.

[nolanpro]

Thanks for the info, i'll take a look at some existing anchors and see if I can measure the depth. Thanks again.

[RTF]

There has to be a mechanical chase in a Maintenance Room. There are pipes going thru the floor somewhere in that building, so that you can measure the floor thickness. Once you determine that you'll know how to size the length of your anchors. You can easily get by with 3/8" - 1/2" diameter anchors.

[nolanpro]

Thanks RTF thats also a good idea. I'm going to check around other places in the common area of my floor. I'm thinking of some fire pipes that I might be able to eyeball a floor thickness if I look straight down the edge of the pipe. If i'm lucky, there might be just enough clearance around the pipe to see.

[tooltroll]

Or check the stairwells; You might be able to see the edge of a slab.

[nolanpro]

Nice! i'll check that also (I actually thought about opening the elevator doors between floors to see the thickness, but checking in the stairwells will set off less alarms haha)