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The Purlin Discussion, Stud names, and plate names got me thinking. I’ve never had a name for something I see all the time.
The vertical member that hangs from the ridge board or at least the top of the rafters and attaches to mid-span of the ceiling joists. Usually in a garage where the ceiling joists are terribly overspanned.
Any names for this thing?
Replies
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king post truss
*Unless it's over a closet, then it's a queen post truss.Gabe
*stiff back or how about cieling tiejim
*Whatever it's name is, I'd like to know exactly what it's FUNCTION is.Is it an attempt to make a truss, without putting in the rest of the webbing? If so, would it really function as a truss?It appears to me to be little more than a brace from the joist to support the ridge board, which normally is a bad idea. A structural beam should be in that location for that purpose.On the other hand, if the ridge board is already braced well, then is it there to "hold up" the joist?If so, that would make sense only if there were one at every joist, or if it were attached to a strongback that spanned the joists.
*Ken, it is a truss, really. It's all in the triangles, connections and, of course, to an extent, the size of the material. King trusses typically can span 20-60 feet.An engineering text book http://members.aol.com/covbr/truss.html#Eng_book deninition of a truss is as follows: "A truss consists of a group of ties and struts so designed and connected that they form astructure which acts as a large beam. The members usually form one or more triangles in a single plane and are so arranged that the external loads are applied at the joints and theoretically cause only axial tension or axial compression in the members. The members are assumed to be connected at their joints with frictionless hinges or pins, which allow the members freedom to rotate slightly."
*Ryan, it is a strut. It's functioin is dubious, unless the connections are engineereed properly which they rarely are.It's one of those items that people like to see because they've always seen them.It might have minimal value in situatioins that don't really require it.blue
*I agree, that it is a truss. The king post you describe is under tension, and the only purpose it serves is to keep the wall ties from sagging. It definitely sounds like it's not designed for any storage.Steve
*Thanks for the link Ralph, it led to some interesting reading.Gabe
*You got it all wrong Gabe - It's a Kingpost in most of the country. It's only a "Queen" post if it's installed in L.A county by a guy wearing an earring.
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The Purlin Discussion, Stud names, and plate names got me thinking. I've never had a name for something I see all the time.
The vertical member that hangs from the ridge board or at least the top of the rafters and attaches to mid-span of the ceiling joists. Usually in a garage where the ceiling joists are terribly overspanned.
Any names for this thing?