The trusses provide NO significant bracing - if no sheathing was installed, the framing could easily be straightened.


As I've said before, I agree that if the sheathing was on a horizontal or nearly horizontal plane, it wouldn't be practical to even TRY to straighten it with cables. Your example doesn't apply to this discussion because the sheathing is on a significant slope - the desired movement is in the horizontal plane - not on the plane of the roof slope.

I'm not even going to try and figure that mathematically. I've laid a lot of roof plywood and I can tell you if you are bowed out 5 inches in 16 ft and your plywood is laid to the fascia you are going to have a pretty good gap at the bottom between the second sheet and third sheet. (0.034 in. is ridiculous).


Also you are considering straight lines which it is not, it's bowed.

And if you start the next course flush with the gable end you are going to have a hell of a gap between the first and second course. Like a 5 inch gap 16 ft from the end of the roof.

Where the heck are the framers? Ernie?

And I say the desired movement is also on the plane of the roof slope between the fascia and the ridge line. You still have a 14'(?) X 32' rectangle you are trying to straighten regardless of whether it's lying flat or inclined.

Taking that statement into consideration.....

The 'framers' could POSSIBLY set one wall overhang at 16"
(we're speculating here, thinking they may have had a beer or 4)

If that was the case, they would PURPOSELY bow the other wall
out to match the 16" overhang ......?????????

Just doesn't seem possible, EH?

Boggles the mind.....

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I'm not too sure what you're saying here "The 'framers' could POSSIBLY set one wall overhang at 16".

Overhang is determined by the "tail" of the truss. Trusses are set with the "point" (intersection of the horizontal seat and the slope of the tail) flush with the outside edge of the top plate.

What probably happened was the back wall was pushed out when they were sliding the trusses up and then toenailed down with the seat where it should be. Meanwhile the guy on the front end of the house lines up the seat with the top plate duplicating the shape of the back wall. Or after the trusses are up and not properly braced they were pushed back by something.

The least likely scenario is the walls got bowed AFTER the plywood was installed. I'd be inclined to use impossible here rather than "least likely"

We once racked a prefabbed place 3/4 inch. Place came with siding and windows all installed. When we put up the trusses we didn't realize we moved the wall 3/4 inch out of plumb and when we did the attachment at the opposite wall the seat goes where it belongs duplicating the configuration of the other wall.

Your comment about setting the overhang at 16 inches and then duplicating on the other wall is wrong.

The truss may not have had a 'drooping' tail....I don't know....haven't seen it.

Kingray originally speculated on the "measure 16" (way up there ^^)
I was just using that info....

Since you stated your issues on the 3/4 inch rack,
Can you really expect someone to walk away from a job with 3 INCH Rack???

Pictures gonna be worth well more than 1000 words

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I really don't think so. I'm basing that on the guy is accurately describing the situation which is not that complex.

He said the walls are bowed out about 5 inches or so. A picture of a wall bowed out 5 inch isn't going to tell us much more than we already know and we'll still be divided as to "as built" or after built". We'll see

A photo of a string showing a 5" gap isn't going to do anything but confirm the top of the wall is bowed.

Photos of sheathing relative to studs and trusses... Photos of sheets of wood custom cut to fit... Now THAT might reveal something.

You're absolutely right on both counts. I'm just curious to see the extent of the bow. If the plywood is visible from the bottom (no drywall ceiling) a picture of that first course may tell the story.

Oh!

I check back here every 5 minutes or so waiting for KingRay's great unveiling!

And yaaa... I want to see the extent of the bow too.