Stiffener plates on trusses

[mathew stouffer]

This home was built in 1995. I typically do not see this, is it acceptable or is this considered an unapproved field alteration. It sure did look purtty;)

[Kary Krismer]

What are the boards that cross through the gaps? It almost looks like they were trying to suspend something from the trusses.

[Steve E Zabarylo]

What are the boards that cross through the gaps? It almost looks like they were trying to suspend something from the trusses.


j) Roof truss bracing—web members longer than 6 ft.
(1.82 m) require bracing. This bracing consists of a 1 in. x 3
in. (19 mm x 76 mm) nailed with two, 2 in. (50 mm) nails
across all of the compression members for the full length
of the roof.

The trusses may have had a rough ride to the site and the manufacturer authorized the plywood gusset reinforcement to keep the code wranglers happy. There has to be a letter on record with an engineers signature for the modification.

Them are some wicked collar ties!

[H.G. Watson, Sr.]

Strong backs and field applied gussets/plates (not stiffeners). Cannot apply factory type metal truss plates in the field. Plywood is often used for this purpose.Multi-piece truss system. Non-storage type high pitched and tall attic space, made in two parts so can be shipped to site. See drawings (and notes thereon) for specifics.

[mathew stouffer]

Thanks guys. Kary the boards for to TV equipment and other crap they had up there. I didn't hang around that long to check it out, it was 138 degrees.

[H.G. Watson, Sr.]

Thanks guys. Kary the boards for to TV equipment and other crap they had up there. I didn't hang around that long to check it out, it was 138 degrees.


No, they are NOT FOR that.

The rows of 4x2" stress-graded lumber are permanent bracing, specifically Continuous Lateral Restraint (CLR) for the supporting trusses along their TOP CHORD, and would be indicated on the Truss Design Drawing(s) (TDD(s) (possibly via note referring to summary sheet)!

There may also be tags applied to the Engineered Trusses themselves indicating locations.

All top chords require permanent restraint/bracing for all the top chords in a piggyback assembly.

The restraint might be accomplished by:

Rows of 4x2 stress-graded lumber CLR and Diagonal Bracing (as we see here for the supporting trusses), or

Connecting the CLR into the roof diaphragm, or

adding Structural Sheathing or Bracing Frames, or

some other equivalent means.
Diagonal Bracing at 10' intervals or less, as specified on the Truss Design Drawing(s) (TDDs).
CLR at spacing specified on the Truss Design Drawing(s) (TDDs).

Pictured in MS's photos:

The upper, or CAP TRUSS is PIGGYBACKED to the lower SUPPORTING TRUSS.

Plywood Gusset/Plates connect the two trusses. CLR on the top chords of the supporting trusses.

Dead and Live Loading should not exceed what is indicated on the truss tags themselves in the areas they are tagged, and in lieu of truss tags what AND WHERE is indicated on the TDDs, in lieu of neither, there should be NO ADDITIONAL LOADING TO THE TRUSSES (including DIY'd inside antenae).

[Kary Krismer]

Dead and Live Loading should not exceed what is indicated on the truss tags themselves in the areas they are tagged, and in lieu of truss tags what AND WHERE is indicated on the TDDs, in lieu of neither, there should be NO ADDITIONAL LOADING TO THE TRUSSES (including DIY'd inside antenae).

I once killed a deal of an agent I was mentoring by pointing out that the bonus room added by the owner above the garage was apparently affecting one of the trusses. It was bending laterally at the bottom (top of what would be the garage ceiling), toward it's neighbor and away from the other. The inspector (found by the buyer) hadn't noticed that, but when it was pointed out did mention design for live loads, and it scared off the buyer (probably rightfully so given their intended use of having a lot of people in that area).

Anyway, assuming you're worried about the weight of an antenna, I would guess you would concur! :D

BTW, it also obviously didn't have sheetrock under that added living area.

[Jerry Peck]

If I read what you were asking ... you are referring to the gussets which were applied to the piggy-backed trusses.

When trusses are too tall ('too wide' when laid on the truck for transporting to the job site) the trusses are made in two sections for transporting, the upper truss is then installed piggy-backed on top of the main truss, with the method of attachment being up to the truss engineer, but most of what I have seen used the plywood gussets like shown in your photo.

[H.G. Watson, Sr.]

The supporting trusses are first installed, and permanently restrained on their top chords, and diagnonaly braced webs when/where required on the supporting trusses (and temp restrained below) BEFORE the cap trusses can begin to be installed, gussets come after when installing piggyback trusses.

[Joseph Ehrhardt]

We have retro fitted plywood gussets like this due to some transferred truss movement,but not that many,they look a foot apart. If code enforcement climbed up there and did their framing inspection and failed it, so then it was retro fitted...hats off to that guy.

The architect may have encountered this issue in the past and not relying adequate framing techniques, had them added. They are pretty for sure, nice job.

[Jerry Peck]

Due to the number of gussets


Those are there to tie the piggy back truss to the main truss below - see H.G.'s post as he went into further detail than I did in my post.

[H.G. Watson, Sr.]

JR, The truss designer and building designer have accomodated a heavier concentrated load at the center. Note cap truss and support truss webs line up, gussets on either side there are for continuous vertical web.

There is nothing to indicate any "red tag" issues. SoP for this type application. Realize you are out of your element. This high pitched tall roof is up in SKI (and SKY) country. Snow loads beyond your TX experiences I'd bet.

See Building plans and TDDs.

[Joao Vieira]

I would buy this house without thinking twice about this. But then again, I already have one.:p

[mathew stouffer]

Thanks for all the info.

[Door Guy]

If I read what you were asking ... you are referring to the gussets which were applied to the piggy-backed trusses.

When trusses are too tall ('too wide' when laid on the truck for transporting to the job site) the trusses are made in two sections for transporting, the upper truss is then installed piggy-backed on top of the main truss, with the method of attachment being up to the truss engineer, but most of what I have seen used the plywood gussets like shown in your photo.

Agreed Jerry, the top trusses are piggy backed because of the height for hauling. The gusset plates may have just been added by the contractor and not even required. If your concerned note it and suggest SE to look at.

[Mike Truss Guy]

That is one of the best constructed and correctly installed cap truss connections that I have seen. This connection detail is typically included as any truss engineering package which include a "piggyback" or "cap" truss.

Those plywood gussets are excellent. The fact that they did not forget the continuous lateral bracing is also heart warming. Well done.

Now that TV antenna scares me. ;)

[Joao Vieira]

Now that TV antenna scares me:D

Is it code compliant under the roof like that? The owner might be alien.
I have been waiting to have a alien assistant with infrared + x-ray vision to do my inspections.

[Joao Vieira]

http://imghost.indiamart.com/data/U/V/MY-16491/wood-working-vice_250x250.jpg ol school press should work flipped on opposite sides of the plates since the top has tendency to apply less compression

[Mike Truss Guy]

That is old school. The forces needed to press truss plates is very high. Eagle Metal Products makes a pretty good portable press.

http://img827.imageshack.us/img827/8159/frp35.jpg

Eagle Metal Products | Engineering, Fabrication and Equipment for the Building Component Industry (http://www.eaglemetal.com/field-repair-press.php)

[Joao Vieira]

That is indeed a good looking press for highly productive work . The press below is just for smaller scale work and for amateurs like me :p

http://www.abmtools.com/images/Wood_Working_Accessories/Wood_Working_Vice.jpg