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J. Clarke[_2_] J. Clarke[_2_] is offline
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Default Shear strength of screws

In article ,
says...

On 12 Apr 2012 01:17:25 GMT,
(Scott Lurndal)
wrote:

writes:
On Wed, 11 Apr 2012 20:05:15 -0400, tiredofspam nospam.nospam.com
wrote:

Used to be that framing had to be toe nailed...
Now I see nails used from top and bottom sil to studs. Not as strong.
The toe nailing really locks it in from both sides.
straight nailing will not withstand storm forces as much.
But then again, most roofs will easily lift before the framing gives.

On 4/11/2012 7:37 PM, Swingman wrote:
On 4/11/2012 6:33 PM, Larry Blanchard wrote:
On Wed, 11 Apr 2012 14:26:06 -0700, RP wrote:

Up here in the Northeast, if we are framing a house, we cannot use
screws. Must use nails or you will not pass the framing inspection.

That seems a little strange - what's the rational given, if any?

Nails generally have a greater shear strength than screws, thus the
requirement in some areas are very specific as to the nails used, their
size, makeup, and nailing patterns.


I learned the hard way that any carpentry (as opposed to ww) work I do,
someday I, or someone who comes after, will have to take it apart again.
I use screws for all that now.


A straight nail driven into end grain has about the same holding power
(in tension) as yesterday's chewing gum.


When it is nailed from the top plate or sill into stud endgrain, it suffices since
the roof holds them together - the nail is to keep the stud aligned, any forces
will be perpendicular to the nail.

Untill you get wind lift. Or siesmic activity. Which is why
toe-nailing USED to be pretty well a requirement in the days of plain
nails. Ardox nails help. TimberLok screws can be used in place of
hurricane straps to connect trusses to sills. Fully code compliant,


For certain values of "code". Building codes in the US are not
standardized. There is a model code but no requirement that it be used
by any given locality.

and you won't mistake them for a common screw or lag bolt - and you
don't need to remove them or X-Ray to know how long the timberlok is
(they are clearly marked on their black hex heads)