Re: Hole Diameter for running cable

["B Fuhrmann" <b-fuhrmann-usenet@xxxxxxxxxxxxxxxxxxxxxxxxx>]

"Robert Green" wrote in message ...
>
> You don't need to restore the joist strength for 2" holes.  Just keep
> them away from the center 1/3 of the joist and at least 2" apart from
> each other.  Also, stay near the vertical center of the joists.

I have seen this posted several times and it could be misleading to the
reader or it is wrong.

By "center 1/3 of the joist", I am assuming that you really mean the center
1/3 of the span where the stress is the most.

The holes SHOULD be in the center 1/3 of the joist, measured across the
width of the board.
As others have pointed out that is where there is very little stress on the
board.


---- The origonal poster has also commented on knots being a problem.  This
is for him.
A lot depends on the condition of the knot and it's location.  A knot that
is not loose or cracked is much less of a problem than a loose or cracked
one.  The tight knot will still disrupt the stress pattern but much less.
Knots that are towards the top of the joist are in compression.  I that
location, they are less of a problem.
A loose or cracked knot at the bottom edge of the joist is in tension and is
almost equivalent to a notch there.

For strengthening the areas that you are unsure of, I would recommend the
spike plate material that is used in building truss framing.   It is strong
and does a good job of marying the stress to the area under it with many
"nails".
----


>> I am installing a new Hayden central vacuum...
>
> Beware.  Hayden can sometimes be a royal pain when you need repair
> parts or warranty service.  We dropped them after a couple of
> run-arounds.

It's good to hear results from the real world about how companies handle
customer service.

>> I've always wondered why something as important
>> as building codes are not available on-line...
>
> Many communities now post the IRC code online.  Google a question such
> as "what is the maximum hole diameter in a floor joist" and you'll get
> a lot of opinions plus several municipal code websites with the
> standards.

I suspect that many are not online because they are not complete unless they
are posted by the lowest level of government in the area.  If a state posts
it's code, it could mislead people who do not understand that individual
localities can add or change sections of it.