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Re: Need advise on adding tension rod to wood beam to control deflection

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>A client built a custom home about ten years ago. He installed a 6x14" DF#1
>beam through the livingroom to span 27 feet. The beam was supported at each
>end and with a column in the center - 13'-6" each clear span.
>A new homeowner wants to remove the center column. The original builder is
>on the scene and wants to consider an alternative to replacing the beam or
>adding a beam below the existing.
>He suggested the installation of a tension rod at the bottom of the beam to
>pull the beam up level. I've done similar in truss repairs, but don't feel
>comfortable with this since it would either rely up lag bolt connections at
>the angled plates on each end or require the contractor to plate the top and
>bottom of the beam and drill through the 14" member. The top is probably
>already solid blocked which would make the installation of the top plate
>difficult.
>Any suggestions.
>Has anyone tried using 1/4" steel plates on both faces of the beam and
>stitching through with machine bolts (similar to a flitch plate design)?
>I could use some advise on this one.
>Dennis Wish PE
>
Dennis:
I have run into this situation several times and had good success using
full span steel channels bolted along each side of the timber member.  The
end detail for the channel is set up such that full bearing is provided on
the top of the timber member, and it can be tightened to preload the steel
member.  If you are interested I can e-mail you the detail directly.  The
above assumes that the timber member is situated below the joists rather
than having the joists framing into hangers on the face of the timber.
Selection of the steel channels is based on relative stiffness of the
composite beam, and distribution of forces to the steel and timber as
appropriate.
Best Wishes.
Craig Funston S.E.
Geiger Engineers