On 7/28/2012 9:19 AM, Dave in Texas wrote:
"Swingman" wrote in message
...

On 7/28/2012 6:17 AM, Dave in Texas wrote:
"Leon" wrote in message
...

Well you either knew how to build homes or you did not. These homes in
the Texas area still look relatively good. You seldom see any
indication of foundation problems or cracks in the brick. I have
probably helped to repaint the interiors of a dozen of these homes and
they still look great, no cracks in the sheet rock.

That would explain why I see Nolan Ryan pitching Olshan foundation
repair every time I turn on the tube.
Actually, foundation failures are very common in the Houston area.

We were discussing tract homes built in the 50's to mid 60's. Those did
not have post tension slabs, which are the majority of the slabs that
Olshan specializes in. PTI slabs became ubiquitous in this area in the
late seventies, and are the one's that pay Nolan's fees. Almost every
tract home built in this area since then has a PTI slab.

You are right about the high failure rates for post tension slabs
and I will certainly take your word that those are Olshan's
bread'n'butter. I well remember Tom Tynan preaching the the negatives
of the post tension foundation when he blew into Houston back in the
early 90s (?) all the while he was selling Du-West Foundation Repair. I
grew up in a 1953 tract house (South Post Oak and Willowbend) that
years ago acquired a slew of concrete piers (before they started driving
the round concrete blocks into the gumbo) and my current 1957
[non-tract] NW Houston, one-story ranch has 23 piers under it, done
before I bought it in 1990 (me bad for buying into that).

Post tension slabs are theoretically great for this expansive clay in
Houston, but the spec's have to be religiously followed. Since most of
the developers now use subs who do turnkey slab work, and who do nothing
else, they should have the science down, so now they are generally much
better slabs than they used to be.

Although I will not build with a PTI, if you do things correctly you
should have a pretty good slab. However, most don't builders around here
don't bother to get out of their air conditioned Lexus, take their
blazer off, and follow through.

Biggest problem is getting the concrete at the spec'ed mix (not as big a
problem as it used to be), and in a timely manner (a traffic jam on a
particular day can be the cause of a slab failure years later). A "hot"
load, or one that has to be watered, will develop stress cracks before
the spec'ed time to tension the slab, which does not forebode well for
the future.

When it comes to foundation slabs, I'm on of the few builders around
here who requires test cylinders for every load, has an engineer's tech
on site during the pour, and one of the rarer ones who actually has the
cylinders tested at 7, 14 and 30 days to insure they meet the
compressive strength requirements of the Foundation Plan. (the old
builder trick is to put the concrete contractor on notice that you're
taking test cylinders for the pour, but then either don't take them, or
don't bother to have them tested if you do).

Since the above generally adds about $800 to $1K to the cost of the
house, no modern tract home builder is going to go to that expense in a
subdivision.

In all the times I've done cylinder testing, it saved my bacon on only
one occasion, but it was worth all the money previously spent on
testing, guaranteed.

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