Drill a hole through concrete wall

[blockqoute]

Hello,

I need to drill some holes through a concrete wall and I'm wondering first of all if it's possible? It's a wall about 20 cm thick that I need to get through, and the holes need to be 1-1.5 cm in diameter.

If it's possible, can it be done with a regular hammer drill and hammer drill bits, and then by drilling a hole from both sides of the wall (so they meet in the middle)?

 

[haavard]

It works. Buy a drill (designed for stone/concrete) that is long enough to drill the entire hole from one side.

 

[Freco]

It can be added that you should not use a hammer drill as it is only theoretically possible to achieve what you want with such (in practice, it costs too much in terms of drills, sweat, and frustration to drill such a long hole with a hammer drill).

What you should use is a rotary hammer, which you can either buy or rent (renting doesn't cost much over a weekend).

 

[blockqoute]

Thanks for the answers! Lucky that it is exactly a rotary hammer I'll be using

Freco: Do you think it will be easier to drill everything from the same side? No risk of it cracking on the exit side?

 

[sussox]

We have half-meter drills for our fine Hilti rotary hammer here at work, so it sure works

 

[Freco]

It will definitely be easier to take it from the same side, very difficult to find exactly the right spot if you go from two sides.

As for whether it will crack, I can't answer that, someone more knowledgeable should do so... One might think the risk is greater if it is a plastered side compared to a concrete one (though I don't really have any actual idea about that).

 

[Jan-Å]

If the wall is plastered, it will crack, but with a diameter of 10-15 mm, there's not much to be done. Drilling from both sides and getting it right is, as "Freco" writes, probably very difficult if not impossible.
But it's just a matter of patching a bit or applying some new plaster, not a difficult job.

 

[anaitis]

Place a backing on the exit side.
A piece of wood held in place by some suitable construction.
This way, you won't tear up the exit hole.