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Cantilevers through a solid beam

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As I understand it, you need to extend the roof 16" beyond a 16" deep 
Parallam beam and support a parapet at the end of the roof extension.  That 
means that the facia at the face of the parapet is going to be greater than 
16", so I don't see where that is a limitation.

Suggestion No. 1:  Connect the rafter to the Parallam with a strap over and 
nailed to the back side of the Parallam and support the end with a "kicker" 
running from the bottom of the Parallam to the end of the rafter.

Suggestion No. 2:  Same as suggestion no. 1, except tie the rafter to the 
Parallam with a Simpson LTT (or similar).

Suggestion No. 3:  Run a diagonal member from the top of the Parallam to the 
top of the parapet, a horizontal member from on top of the Parallam to the 
parapet, and a diagonal "kicker" from the bottom of the Parallam to the end 
of the horizontal member.

Suggestion No. 4:  Ask a carpenter how it will be framed.

A. Roger Turk, P.E.(Structural)
Tucson, Arizona

. > I have a design problem where I need to build out the face of a patio from
. > the supporting beams by 16" - and add a parapet above this. The problem is
. > that the total depth of the beam and roof framing is limited to 16 inches 
. > - which happens to be the size of the Parallam required for a 24'-0" 
. > span. The back-span of the rafters is less than 15 feet and the 
. > cantilever is suppose to be, as I mentioned, 16 inches.
. > 
. > An idea came to me that I wanted to run by this group.
. > 
. > I need to extend at least a 2x4" member over the beam - which is not
. > possible because of the restricted depth. Since this is the compression 
. > side of the beam, I thought that I might be able to notch out the 2x4 in 
. > the top side of the Parallam (3.5" depth) and extend the 2x4's through the
. > beam. When loaded, the beam will be in compression and the bottom of the
. > rafter is above the neutral axis so that it remains in compression. I can
. > strap this to compensate for a possible uplift by wind or seismic that 
. > might place the upper side of the beam in tension.
. > 
. > Any thoughts on this?
. > Any better suggestions?
. > 
. > Thanks,
. > Dennis Wish PE
. >