best way to constuct knee wall to support rafters...

[jimtheengineer10]

A client wants to install a new roof on a trailer. He want to increase the ceiling height by about a foot. The lumber supplier told him to build a one foot tall wood stud knee wall on top of the existing wood stud wall and then have the rafters attach to the top of the knee wall. My initial thought was this creates a hinge point type connecting between the proposed knee wall and the existing wall. Am I overthinking this or will this work if the knee wall sill plate is fastened to the existing wall top plate with bolts every 16" o.c. or so?

One other thought I had was to cut thru the top plate next to each stud and sister a 4' long wood stud to the existing stud (3' sistered to the existing stud and 1' of the new stud extending up ). See the attached pdf.

Thanks.

 

[AELLC]

http://eng-tips.com/viewthread.cfm?qid=362118

 

[CELinOttawa]

I should really request a membership in Pat's Pub... Never have gotten around to it... lol

 

[AELLC]

They even let riff-raff like me into it, so it may be easier than you think.
I have a number of frivolous threads going there.

 

[XR250]

You are also adding another foot of sail to the already crappy MWFRS. Make sure the new roof gets attached to any interior shearwalls (if they exist on this one)

 

[CELinOttawa]

Well AELLC, looks like I'll not be debating anything in the Pub... I've had a request in for nearly a week, and still no answer.

Me thinks someone doesn't like me!

 

[XR250]

I have also given up trailer jobs.

 

[AELLC]

CEL, you are way up in the MVP list, but maybe they want members with earlier start dates - you seem recent. Sorry.

The definition of a structural engineer: overdesign by a factor of 1.999, instead of the usual 2.