Is there a way to make sure it's not PT slab? It's a single story single
family residence, probably unlikely to be PT?

MC

"RicodJour" wrote in message
oups.com...
miamicuse wrote:
The plans in the city says 8". I am not positively sure. Probably will
run
into rebars?

If you're in FL (likely with that monniker) and you have an 8" thick
slab, you may have a post-tensioned slab. You do NOT want to go
cutting into that slab willy-nilly.

This from a post a few years ago by DanC:

Dan Jul 2 2003, 2:13 pm show options
Newsgroups: alt.building.construction
From: "Dan" - Find messages by this author
Date: Wed, 2 Jul 2003 11:27:07 -0700

You damn well better believe there's a reason NOT TO CUT OR DRILL!
Depending
on the design specs, PT cables can have as little as a few hundred
pounds of
tension on them or as much as hundreds of thousands of pounds of
tension on
them. PT cables are as inherent to the structural strength of the slab
as is
the concrete. While you 'MAY' not see a catastrophic failure by
accidentally
cutting a single cable, you will suffer some design deficiency that may
eventually lead to catastrophic failure. Think of that cable as a big
rubber
band that's stretched to about maximum and then cut. What happens to
the
rubber band, other then it's cut? Uncontrolled release of energy! If
you've
ever seen those 40~ 80 foot post tensioned concrete beams being
transported
down the highways, you'll notice they usually have camber in them.
(Humped
up) Your slab is much the same way. It's a somewhat common practice in
multi
storied structural steel framed buildings utilizing pan slabs.

Were this my house, those doing the work would get & have an engineered
design drawing detailing EXACTLY the procedures required to undertake
this.
None of that freelance BS and shoot from the hip. You haven't lived
till
you've seen a slab or beam blow apart while undergoing PT. Can you say
concrete missiles? (although it is rare)