Roof Truss


capitaldesigns
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I am doing a small room addition project using roof trusses. When I do a section through the addition I see that the

trusses are drawn with a lower cord that extend beyond the exterior wall by 8 to 10 inches. 

I need the lower cord to stop at the outside edge of the exterior wall. Is there a setting that controls if the lower cord

stops at the wall or extends past the exterior wall.

3D Framing.bmp

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Do you have a shallow energy heel on your truss?  Depending on your roof slope, if your energy heel is more than about 8" it will stop the bottom cord at the wall.

Alaskan_Son just recently posted information about how to do what you're asking in a recent truss-related question here.
I would recommend looking for Alaskan_Son's recent posts for his work-around.

 

Here's a link to the post I refer to... you'll need to scroll down a ways 

 

Edited by DzinEye
more info...
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Here is a framing perspective of the trusses. 

I see another problem. The last 5 trusses are elevated.

The top cord should be sitting on top of the lower cored.

To the right is an existing garage also with trusses.
The 2 roof planes meet at the wall where the trusses are shown.

This will create a valley with a cricket above. Is the 2 roof plans

coming together raising the upper cord 8 to 10 inches above the

lower cord ? If so, why ? How to I get the upper cords to be lower.

 

And I do not have the energy heel option checked.

 

Truss Framing.png

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One way or another you need to lower the roof plane.  Trusses will build between the ceiling plane and the roof plane.  Possibly your default is for 2x10 or 2x12 rafters so that may be your framing thickness.  Difficult to know for sure without the plan file.

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17 hours ago, capitaldesigns said:

Here is a framing perspective of the trusses. 

I see another problem. The last 5 trusses are elevated.

The top cord should be sitting on top of the lower cored.

To the right is an existing garage also with trusses.
The 2 roof planes meet at the wall where the trusses are shown.

This will create a valley with a cricket above. Is the 2 roof plans

coming together raising the upper cord 8 to 10 inches above the

lower cord ? If so, why ? How to I get the upper cords to be lower.

 

And I do not have the energy heel option checked.

 

Truss Framing.png

 

This is from a different post:

 

 but keep in mind that the location of the baseline in plan view matters as well. You really shouldn't need to think about the baseline. Rather, all your rooms should have the same ceiling height. Then, you'll want to make sure your roof height factors in 2 things for trusses:

  1. Raise / lower from ceiling height (for my region that is typically 3.5") or think of this as the bottom chord depth
  2. Roof Layers / Structure (for my region that is typically 3.5") or think of this as the top chord depth

These 2 items will help you define the heel height of the truss - which matches Chief's Baseline height. This is the vertical height to the underside of the roof sheathing at the exterior of the framing layer. Then, any roof plane you draw will have the correct 'Baseline" relative to the top of the wall that the roof plane was drawn over.

Quick example: In my region, the typical truss has the top chord 'pivoting' on the outer edge of the bottom chord.

image.thumb.png.4018f34eaedad764db3c11ad857689bf.pngimage.thumb.png.63d687a677e61715332676d51a8f61c8.png

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