Right way to do ceiling strapping with autoframe?

[GeneDavis]

I specified my porch ceilings, which I want to finish in LP panel fixed to 1 x 3 strapping, in the FINISH part of structure, 3/4-thickness framing layer, 16" centers, 2.5" wide, above the 0.354 panel.  This is a change.  I formerly specified the ceiling finish as a single later panel, fixed directly to the truss chords above.  

 

I try autoframing the room's ceiling and do not get the strapping I expect.  What might I try next?  I've framing built everywhere else and have edited quite a bit, so I only want to frame these ceilings.

[ValleyGuy]

On 7/6/2025 at 5:29 PM, GeneDavis said:

I specified my porch ceilings, which I want to finish in LP panel fixed to 1 x 3 strapping, in the FINISH part of structure, 3/4-thickness framing layer, 16" centers, 2.5" wide, above the 0.354 panel.  This is a change.  I formerly specified the ceiling finish as a single later panel, fixed directly to the truss chords above.  

 

I try autoframing the room's ceiling and do not get the strapping I expect.  What might I try next?  I've framing built everywhere else and have edited quite a bit, so I only want to frame these ceilings.

Hey Gene,  I went through this with Support a couple of years back. Strapping the rafters with 1x4 @ 16" o.c. is the industry standard here. At that time, and I believe it to still be the case, CA isn't able to auto frame 1x4 that is in the ceiling layers. I made and saved the two different 1x4 framing materials in my library and manually frame when needed. As the framing is actually in the ceiling layers, this was the only work around that I have come up with that keeps my top plate storey pole dimensions correct.

 

Let me know if you find a solution,

Shayne

[GeneDavis]

Thanks, Shayne.  I framed manually, really only to be able to show it in a 2D floorplan detail.

 

I'm told that everywhere in the New England states, builders strap every ceiling, even those when the members they are strapping over are 16" on center.  I guess lumber and labor are free in Massachusetts.

 

Interesting that Chief lets you put a layer there in ceiling finish with the "framing" option checkbox, which opens the on-center-spacing dialog box for spec, but then does not autoframe.  Maybe I'll write a suggestion.

[Rookie65]

Yes, strapping is used all of the time here in MA. I think it helps being a smaller size than the joists, so movement is less noticeable with shrinking, etc. Plus it's a good place to run electrical wire between the joists and drywall.

[ValleyGuy]

17 hours ago, GeneDavis said:

I'm told that everywhere in the New England states, builders strap every ceiling, even those when the members they are strapping over are 16" on center.  I guess lumber and labor are free in Massachusetts.

I came east from the west and thought that it was really different at first. There definitely are some advantages though. Having a completely open space with nothing but exterior walls and rafters to apply 20' wide poly is a lot faster than VB individual rooms or dealing with tie in wall plates from perpendicular walls. If the poly is tacked to the rafters only where the 1x4 will sandwich it to the rafter, there won't be any staple holes from the weight of the attic insulation. The ceiling doesn't receive any errant DW screw holes nor does it get any electrical wire or fixture box holes. Only stink pipe stack and sometimes HVAC penetrations, so it makes for a pretty tight ceiling. Push the stack through the roof and drop any necessary HVAC leads (plus the stack) below the ceiling level while the roof is being shingled. As the strapping supports the weight of the R50 in the ceiling, a double studded or ICF wall configuration means that you can have an insulated and VB house shell with the heat turned on before any back framing is done! Way nicer environment in the colder months. Any "extra material and time cost" applying strapping is more than recouped. I think it makes a much better built house having the heat on so early with the winter time builds.