Some years ago, I heard a story that was spooky, in how true it could be. A
couple fire department guys were visiting a building site. Being friendly,
and helpful. Hope it didn't catch fire, but wanted to know what's going on,
just in case.
The fire department guy noticed all the wood cribbing, and frame to hold up
the cement floors. Looks, and sees that it's post (post "afterward", not
like fence post) tensioned concrete. He asks if they have post tensioned the
The construction workers looked blank. And then said no, we havn't gotten
around to that. We're too busy jacking the cables.
When sky scrapers are built, often the floors are held up by wooden frames.
If the wood catches fire, and burns away, the building will collapse. That's
important fo the fire department guys to know.
Christopher A. Young
Learn more about Jesus
For the size of the hole that you need it may pay to hire a concrete cutting
and drilling company to diamond drill a nice round hole through the concrete
with little mess and dust. As said above, there will be steel in the
concrete, re-bars can be OK, but be cautioned about cutting any tensioning
cables as that could be a problem. It may take an engineer to identify what
you have, it they can without opening something up to check it out, and
possibly identify where you can drill to avoid the tension cables.