bernie

rafters / trusses spanning length not width of roof

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in attached .plan file have a simple rectangle building with mono sloping roof in 1 direction

I want the (steel) rafters to NOT slope upward from low end to high end (as per normal timber rafters)

BUT

span the length of the building and "run up" the roof following the slope of the roof.

 

i thought the joist direction tool allowed us to specify which direction the rafters would run???????

when using the build/framing/roof framing tool, but I cannot get it to have any influence,

im sure I have used it in the past on prior versions of ca??

 

so for the demo plan attached I manually drew a rafter at ridge and then multi-copied it down the roof to the gutter.

 

ya so does anyone know how to get the joist direction tool to influence roof rafters ?

(or better still - truss direction on a per roof plane basis? (for parallel chord trusses running across the building not up/down)

 

cheers,

Bernie

 

 

Untitled 1.plan

post-526-0-60906300-1435730977_thumb.jpg

post-526-0-21506100-1435730985_thumb.jpg

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I think rafters are hard wired aren't they ? (low to high point ) so I don't think the joist tool or the framing ref. tool work , but Trusses are drawn manually and don't care as long as there is a roof plane and a ceiling plane for them to build between , not sure if there is a minimum depth though on a flat roof ?. It might require a 0" height 2nd floor and the use of floor trusses instead perhaps?

 

M.

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Go to framing, select general, select roof, select build roof framing. I made no changes in your plan and it framed your way. I had to delete your roof framing and I changed joist to steel.

post-4392-0-48052300-1435758346_thumb.jpg

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Select build frame, not general in your framing icon.

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Go to framing, select general, select roof, select build roof framing. I made no changes in your plan and it framed your way. I had to delete your roof framing and I changed joist to steel.

I think you missed the point.  He wants the rafters to frame perpendicular to the roof slope,  not parallel.

 

The answer.......  build roof,  define rafters as spanning 3568' o.c.,  now put in manual rafters.......  if you rebuild framing,  they should remain.  

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Joists are parallel with roof slope in my reply with attachment. But you are a guru, so you must be right. I say that with much respect.

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I think you missed the point.  He wants the rafters to frame perpendicular to the roof slope,  not parallel.

 

The answer.......  build roof,  define rafters as spanning 3568' o.c.,  now put in manual rafters.......  if you rebuild framing,  they should remain.  

 

interesting Scott , 1st time I have ever seen that tip   , I assume the 3568' is just an arbitrary way larger number ( than building width) that's easy to type on keyboard ?

 

*** I think you missed the slope vs rafter run predicament here too Shane...  he wants to use parallel chord metal trusses running across the building , sitting on raked walls I would assume ...

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Bernie

Did 1 recently where rafters were actually purlins spanning between portal frames. I just went into cross section places cad boxes in the correct locations and then converted them to poly solids and specified the known lenght. I then went back into plan view and adjusted the positions. I also noticed you could convert all at once FYI.

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I believe Shane has the correct framing but the camera angle is throwing off the span direction.

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I believe Shane has the correct framing but the camera angle is throwing off the span direction.

 

You can see from the raked wall framing the rafters run parallel/up the slope not across as I thought the OP wanted?

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ok so the answers Im getting back are to manually draw em process (cant use "build framing" tools..)

yes Graeme - rafters as steel purlins between slightly raking portal frames is exactly what Im doing..

Yes Scott - should convert my framing to coloured framing as you do :)

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Didn't someone recently post how to do this with "Outlookers"?

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Manually Drawn trusses give you raked portal/ truss frames when I tried it , and roof beams or Lookouts done manually should do the rest I think?

 

Perhaps ask Graeme nicely to "share" his plan for tips

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Gang pile on Shane, lol. My way was correct too, sorry I didn't detail EVERY ASPECT. We have to let the person posting thread play too. This forum is a HOOT!! I respect ALL of your advice to me and others.

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