Re: Hole Diameter for running cable

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"Marc_F_Hult" <MFHult@xxxxxxxxxxxxxxxxxxxxx> wrote in message
news:63jrm2tslvp5p5gn4q7nuksoigi8b1cb4o@xxxxxxxxxx
> On Wed, 29 Nov 2006 06:11:08 -0500, "Robert Green"
> <ROBERT_GREEN1963@xxxxxxxxx> wrote in message
> <apGdnVhjMPZi9vDYnZ2dnUVZ_vqdnZ2d@xxxxxxx>:
>
> >"Robert L Bass" <sales@xxxxxxxxxxxxxxxxxxxxx> wrote in message
> >
> ><stuff snipped>
> >
> >>Use nailing plates to protect the wires.  However, these do not restore
> >>any of the strength of the framing member lost by drilling or notching.
> >
> >What does?  How would you run wires in a way that didn't reduce the
> >structural integrity of the framing?
>
> One can use a prefabricated metal gusset scabbed to the joists
and(or)attach
> custom metal or plywood reinforcements to the sides of the framing member.
> This can restore all lost strength and then some.

My predisposition is to clad the affected joist with 3/4" plywood scraps
attached by countersunk woodscrews.  I have a lot of nearly 1' by 4' by 3/4"
scraps from a previous project.  What length of brace would you use,
assuming you're covering the entire height of the joist?

While I probably won't do any bracing for 1" holes or less, the 2" vacuum
cleaner pipes bother me.  I just measured the joists and they are only 8" so
a 2" hole removes a fair proportion of the material.  I hear the floor groan
when Dad visits in his power chair so I am concerned that I might already be
overloading the structure with all the books and file cabinets we have.
Worse, still.  This house was built during the early years of WWII and the
lumber is less than prime grade as much of it went to the war effort.
(These houses were actually part of the war effort, built to house the flood
of clerks that decended on DC to do the war's paperwork.)

> I had to do this because the local yokels who wired our house during a
> 1980's remodeling prior to our ownership cut slots in the (now)
185-year-old
> floor joists in order to route 10 and 8 AWG  wire to AC compressors and
> electric ovens.  They cut through the bottom 2/5th of the joists in the
> middle of the span!

Slots?!  In bottom?  At the MIDDLE?  The HORROR!! (-:  I just ran into the
handiwork of a teenage notched who made smaller, but equally misplaced
notches to run an illegal outlet to the basement room he built for himself.
Imagine a teenager with no code knowledge (and little construction
knowledge) finishing off his own room in the corner of the basement.  He
drilled into the block wall and cracked it to mount furring strips to mount
uninsulated vinyl faced, cheapest grade available fiberboard panel.  As we
peeled back the paneling you could see how water had infiltrated from the
cracked cinderblock and spread mold like the Black Death along the entire
wall.  It was like cleaning up nuclear waste.

> Floor was like a trampoline.  They also used aluminum
> wire which I've now replaced all the way to the third floor. It was a
week's
> work stretched out over 8 years to replace all the wiring and fix the
> structural issues caused by others.

The snow load problem that gave the "This Old House" crew such fits reminded
me of why it's good to overbuild sometimes.  While the long steel beam was
strong enough to support the span and the steel support column was well
anchored and not corroded, there were still long cracks along the wallboard
that appeared only in the early spring.  The time of year eventually led to
the snow load discovery.  They were fortunately able to design the addition
to bear a lot of the load previous borne by the central steel column.  I
guess only a lingering, heavy snowload will tell the true tale of whether it
has been fixed.

It makes me wonder, once again, whether the "self aware" house of the future
will have strain gauges that can alert the homeowner that there's a problem
*before* a crack appears.

--
Bobby G.