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View Full Version : Truss Rafter repair?



RobertSmith
12-03-2007, 04:39 PM
.............

Kevin Barre
12-03-2007, 05:03 PM
Looks like someone decided to add their version of a stiffback. However, why they would do it with (presumably) engineered trusses is beyond me.

Jerry Peck
12-03-2007, 06:26 PM
Was there a wall under that area?

Maybe soffit with cabinets?

Jerry Peck
12-03-2007, 07:00 PM
This is over the master bedroom. Nothing to flag me in there for structural issues.......however,.......homeowner did extensive remodel (poor remodel), moved walls around all over the house.

Yep ... there probably 'was' a soffit hanging down there, probably over the original master bath?

Kevin Barre
12-03-2007, 07:29 PM
That would be one hell of a long, straight soffitt! Assuming 24" spacing, that's at least 12' visible and likely more that we can't see. If we assume that they only hung 2X4 blocks and reinforced the bottom chords where the soffitt was to be installed that would be an atypical bath layout. I don't think I've ever seen a 12' long bath vanity...with or without a soffitt above. I suspect something else. My guess is that some carpenter who didn't understand trusses, at whatever time and for whatever reason, thought reinforcement was necessary. Possibly due to a remodel where interior walls were removed; possibly not. In any case, I see no harm done based on the information given that there were no other signs of distress inside. The bottom chords need to be tied together anyway; think of this as an overly elaborate way of doing it since normally there's just a 2X4 "rat run" installed.

James Duffin
12-03-2007, 08:16 PM
I agree with Jerry. Someone built a box to hide a pipe or a duct.

Kevin Barre
12-03-2007, 08:53 PM
Almost any duct or pipe could have been run through the attic. No need to go through the trouble and expense of building a soffitt to hide them. And, if you roughly scale the photo, it makes it unlikely that the soffitt would have been wider inside than about 10" max. Pretty narrow for any kind of soffitt.

I still say it's an attempt -- needed or not -- at structural stiffening.

Jim Luttrall
12-03-2007, 08:57 PM
This may have been an attempt at creating a slip joint for a non-bearing interior wall to avoid up-lift... just brain storming here.

The key is what is below in the interior.
In any case, I do not see anything cuts on the trusses that would be a problem.

Jerry Peck
12-04-2007, 06:13 AM
Almost any duct or pipe could have been run through the attic. No need to go through the trouble and expense of building a soffitt to hide them.

I agree on those, but ...


And, if you roughly scale the photo, it makes it unlikely that the soffitt would have been wider inside than about 10" max.

... I estimated it to be: 2 - 2x4 (3-1/2" + 3-1/2" = 7"), plus space between those two 2x4 for 2 more 2x4 (3-1/2" + 3-1/2" = 7"), making a total width of about 14", which is roughly typical of a soffit over a standard 12" upper cabinet.

I might go with the 'structural stiffening' if there were no vertical pieces, then I would consider the laterals-on-edge as lateral braces, but here, I think those are just to set as supports to nail the verticals to.

As Jim said, I don't see anything which looks like it is a problem, and, in fact, if there was a soffit there and it is now gone, that is good as that removed weight hanging from the trusses which (I am sure) was not included in the truss loading design.

Kevin Barre
12-04-2007, 07:19 AM
... I estimated it to be: 2 - 2x4 (3-1/2" + 3-1/2" = 7"), plus space between those two 2x4 for 2 more 2x4 (3-1/2" + 3-1/2" = 7"), making a total width of about 14", which is roughly typical of a soffit over a standard 12" upper cabinet.
You're right about the width. For some reason I had a brain failure and was looking at the width to the outside of the 2x6's, not the vertical 2x4's.




I might go with the 'structural stiffening' if there were no vertical pieces, then I would consider the laterals-on-edge as lateral braces, but here, I think those are just to set as supports to nail the verticals to.

That's where we differ. If simple lateral bracing was the goal, it could have been done with a single 2x4 nailed down to the bottom chord or to one of the web members. I think the whole point of the heavier 2x6's carefully installed on edge was to provide resistance to vertical movement. I think the 2x4's are to provide a nailer to tie the webs, chords and braces together, just like a stiffback or strongback is done on stick-framed construction. I still doubt the soffitt theory. Look how the 2x4 braces change sides of the 2x6's near the gable end. If those were there to form the sides of a soffitt it would be one funky-shaped soffitt since it would vary in width from point to point...and I see no framing to form a corner to transition in width at the point where the 2x4's switch sides. In any case, I still say I see no harm...it's just a matter of curiosity.

Jerry Peck
12-04-2007, 07:30 AM
In any case, I still say I see no harm...it's just a matter of curiosity.

On those two things, I think most of us agree. :D