twoshed

No roof plane truss error

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I am trying to draw a simple truss for a storage shed that is as close as possible to the stamped drawing I have from an engineer. The outside wall edge to wall edge distance is 10 and the roof overhang is 1'. There is a single bottom chord (collar) that is 4' long at the bottom of the chord, that ends up being 1' above the top plate - pitch of 4 in 12 no birdsmouth. I have home designer pro so I think I could do this at least two different ways and I have tried both.

1a) Build the wall, ceiling, and roof to set the top plate height and the roof baseline

1b) Set the room ceiling height one foot higher so that it is at the bottom of the truss chord (sloped ceilings seem to automatically follow the bottom of the roof plane minus the framing height (3.5")

1c) Draw Trusses

2a) Use two sloped ceiling planes and either the existing ceiling or a third sloped ceiling plane that is set for a pitch of 0 for the center 4' of the ceiling. When I do that I put the sloped ceiling (roof baseline that is one side of the ceiling plane) baseline on the outside edge of the wall and specify the outside bottom height to be at the top of the plate with a pitch of 4. Maybe I should be putting the ceiling baseline on the inside of the wall?

The point is I have tried a bunch of different ways to do this with varying results, no of which are what I want. I think there is something wrong with my design on the right side of the roof ridge that is causing problems. In the attached plan, I can't place a truss on the right side of the roof at all because CA doesn't think there is a roof plane there. I realize that I need both a roof and ceiling plane. This is a different error than the one saying that there is not enough room between the roof and ceiling planes to place the truss - I've seen that too.

Previously, I was able to draw a truss across the whole roof and it looked good except that there was an excursion down to the top plate (default room ceiling height) even though I had a sloped ceiling plane over it.

I have been looking for the difference between the left and right side of the roof and framing but I haven’t found it.  In the attached plan a lot of things have been deleted and then manually redrawn to try to narrow down what the issue is but with a fresh rebuild of the roof, etc. I had the same problem.

 

It seems to me that there is a roof and ceiling plane and there is enough room between them for the truss

 

59270b8688a50_Roofwithceilingplanemarkedinheavygreen.thumb.JPG.ea6001badb2441a048a0c394f80da75e.JPG59270bc526f8b_roofandceilinglines-roomfortruss.thumb.JPG.73750dc2453eb468a7e92e53afb2ca35.JPG    floor_plan.thumb.JPG.2268a4f1f41cc94d2c57784c8de46c51.JPG   lake_shed2_93a.plan

 

Any help would be greatly appreciated

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I think you are making this more complicated that is necessary. 1: unless you are a state licensed Structural Engineer it is illegal for you to design trusses of any type (In Texas where I live it is a $5,000.00 fine for doing so). 2: all you need to do is to set the ceiling height at the bottom of the intended truss cord. Then build framing, you can manually edit the framing to better emulate what is actually going to appear if you like without using the truss tool. Trusses are designed by Engineers and constructed by others to be delivered at your site. All your model needs to do is to as closely as possible to look like the finished product. Perfection is NOT required.

If in fact your Engineer or Truss company specifies trusses they can give you details of what the trusses will look like for your plans, they need NOT actually be in the plan in 3D. I do not know any carpenters that use 3D details for framing and such details are purely 2D in nature.

 

DJP

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Like this?

 

Snap14.thumb.jpg.138a0509d90deb97582d09a77079b41a.jpg

 

 

Simple plan done in Pro 2016.

 

Set top plate height (ceiling height). Built roof. Raised ceiling 1'. Drew in truss.

 

twoshed.plan  

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12 hours ago, DavidJPotter said:

I think you are making this more complicated that is necessary. 1: unless you are a state licensed Structural Engineer it is illegal for you to design trusses of any type (In Texas where I live it is a $5,000.00 fine for doing so). 2: all you need to do is to set the ceiling height at the bottom of the intended truss cord. Then build framing, you can manually edit the framing to better emulate what is actually going to appear if you like without using the truss tool. Trusses are designed by Engineers and constructed by others to be delivered at your site. All your model needs to do is to as closely as possible to look like the finished product. Perfection is NOT required.

If in fact your Engineer or Truss company specifies trusses they can give you details of what the trusses will look like for your plans, they need NOT actually be in the plan in 3D. I do not know any carpenters that use 3D details for framing and such details are purely 2D in nature.

 

DJP

David,

 

Thanks for your concern and guidance.  I should have said that the stamped drawing I have is from the truss company.  In order for a permit to be issued I need the entire design to be stamped/sealed, etc.  This "shed" is unique because it spans a drainage swale - it's more like a covered bridge.  I have the drainage analysis complete and accepted.  Now I have to do the same with the structure.  I more or less completed the structural analysis and design but because the span is not covered in the code tables I have to have a PE stamp my drawings.  The PE I am working with has reviewed the structural analysis and is willing to more or less stamp my design but he uses AutoCAD LT and it will save me money if I can give him drawings in .DRW format so I am trying to get the model as close as possible and then go through the workflow below.  I'm good at Visio so I am going to use that to fix up any issues with the DXF, add notes, dimensions, etc.   The drawings I previously submitted were from the HD layout tool but I am not taking that route for this go around.

 

Home Designer Pro -> .DXF -> Visio -> .DRW -> AutoCad LT

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11 hours ago, solver said:

Like this?

 

Snap14.thumb.jpg.138a0509d90deb97582d09a77079b41a.jpg

 

 

Simple plan done in Pro 2016.

 

Set top plate height (ceiling height). Built roof. Raised ceiling 1'. Drew in truss.

 

twoshed.plan  

Thanks for taking the time to do that.  I think I did the same thing (I think) and it worked except that I have a kingpost.  I'll see what the difference is with your example.

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