Diagonal braces

[bagged89s10]

I just had this 35x24 garage built. 10ft high walls and 24ft span trusses. yesterday I noticed if I grab the gable wall and try hard to shake it that I can shake the garage slightly. I think I need diagonal braces on the long 35ft wall and maybe one on each end of the wall with the doors The inspector didn’t say anything.

what should i use to add the braces? 1x4 on the face of the studs seems like the easiest? I do plan to insulate and drywall the garage so I would have to add a bunch of furring strips.

how long do I make them?

how many do I need?

which direction and angle is best?

thanks for your help.

 

[SALIV8]

I thought the plywood helps with that?

 

[nmk_61802]

Are those scissor trusses? If so that end wall should have been framed full height for a few studs, no hinge joint at the top plate.

https://www.mitek-us.com/wp-content/uploads/uploadedFiles/_RedesignSite/Content/documents/engineering/tech-articles/design-tips/Gable%20End%20Hinge.pdf

I don't see angular bracing at the end trusses? This is the min bracing that should have been followed unless you had a different packet with the trusses:

http://www.trussworksllc.net/assets/a07b3.pdf

There is a min of 4' required on each corner at the doors, other wise portal framing is needed. Do you have that? I would guess each of these issues contributes to the movement your are seeing.

Also if the bear min code is followed, interior drywall or sheeting is also needed to fully stiffen building.

 

[The Cobbler]

you should have all the shear you need from the plywood. is the plywood nailed to the studs according to the plans? you will also get a lot of shear from the drywall. I don't think you need to add anything if the plywood has been properly fastened

 

[bagged89s10]

Are those scissor trusses? If so that end wall should have been framed full height for a few studs, no hinge joint at the top plate.

https://www.mitek-us.com/wp-content/uploads/uploadedFiles/_RedesignSite/Content/documents/engineering/tech-articles/design-tips/Gable%20End%20Hinge.pdf

I don't see angular bracing at the end trusses? This is the min bracing that should have been followed unless you had a different packet with the trusses:

http://www.trussworksllc.net/assets/a07b3.pdf

There is a min of 4' required on each corner at the doors, other wise portal framing is needed. Do you have that? I would guess each of these issues contributes to the movement your are seeing.

Also if the bear min code is followed, interior drywall or sheeting is also needed to fully stiffen building.

The truss drawings only call for bracing at the top and bottom chords. The top says structural sheathing or purlins at X spacing. We used 5/8” structural sheathing. Bottom chord says rigid ceiling or 10ft on center purlins. We have 10ft on center bracing. The framers nailed 2x4s for bracing. Maybe how and where they nailed these this isn’t sufficient. It doesn’t say anything about cross bracing or diagonal bracing.

I do plan to nail 1x3 furring strips and then drywall to the ceiling but wasn’t planning on it until either the winter or next year.

 

[bagged89s10]

Are those scissor trusses? If so that end wall should have been framed full height for a few studs, no hinge joint at the top plate.

https://www.mitek-us.com/wp-content/uploads/uploadedFiles/_RedesignSite/Content/documents/engineering/tech-articles/design-tips/Gable%20End%20Hinge.pdf

I don't see angular bracing at the end trusses? This is the min bracing that should have been followed unless you had a different packet with the trusses:

http://www.trussworksllc.net/assets/a07b3.pdf

There is a min of 4' required on each corner at the doors, other wise portal framing is needed. Do you have that? I would guess each of these issues contributes to the movement your are seeing.

Also if the bear min code is followed, interior drywall or sheeting is also needed to fully stiffen building.

What do you mean 4’ at each corner at the doors? Also what is portal framing?

 

[nmk_61802]

4’ from jamb to building corner

The Portal Frame Option

Why this site-built framing detail is essential for bracing openings in garages and other wall assemblies.

www.jlconline.com

For the truss bracing do you have a stiff back and angle brace back to second truss at each end truss. That was the angular brace I was questioning and is shown on sheet B3/ third column

 

[firebirdparts]

So the best direction to brace, to get it out of the way, is flat through the attic. The roof is pretty rigid, and that is already doing a lot, but if you're not satisfied, you can always do more by running 2 by 4's diagonally through the attic. Corner to Corner probably makes the most sense. If you sheeted the ceiling with something solid (not saying you want to) that is even better.

That creates a situation where the entire top of the building has to stay exactly rectangular and if any of it moves, it all has to move.

Then, if you have rigid walls, that rectangle in the air can't move either, because the ridge walls and the earth don't allow it to move. If your walls are fully sheeted, they should be rigid, but you can put diagonal sheeting anywhere on the wall, no harm done.

Having done that, you can still bend the wall in the weak direction, but you can't brace against that and really you shouldn't.

 

[firebirdparts]

Sorry I meant to say "rigid" everywhere it says ridge.

 

[joe_padavano]

The plywood is the shear tie. If nailed properly it provides far more diagonal bracing than any 2x material would.

 

[WNYflyer]

Are those scissor trusses? If so that end wall should have been framed full height for a few studs, no hinge joint at the top plate.

https://www.mitek-us.com/wp-content/uploads/uploadedFiles/_RedesignSite/Content/documents/engineering/tech-articles/design-tips/Gable%20End%20Hinge.pdf

^^^ Are the gable end walls ballooned framed? in other words do the studs run continuously from sole plate to the roof deck such there is no hinge at ceiling level? In reality the way a gable end should be constructed if lacking a diaphragm or some type of horizontal bracing at the ceiling level which would brace a hinged joint.
That being said there are all kinds of garages out there built with a hinge joint that haven’t fallen down but I bet a good many of them move, shake, rattle and roll in a good wind. Often even more of a problem in gable walls with openings due to less structure.

 

[JAB82]

Once you put the ceiling in it will not shake if you cant do it now that's ok it is plenty strong with the roof sheathing if you still want to do something before you install the ceiling you can install 2x4 on the top of the bottom cord of the truss at a angle from the gables to the 35 foot walls make them as long as you can and if you need to use 2 2x4's you need to lap them next to each other by 2 trusses just not on one cord end to end. Another thing you can do is install plywood on the soffit before your soffit material of choice just remember to cut openings in it for venting if you are going to insulate and heat the building down the road this will add a extra horizontal brace to the 35 foot long wall

 

[strutaeng]

Yeah, either brace with 2x4 every 6-8' on top of the bottom chord (perpendicular) to the gable wall, if you plan to add a ceiling on the bottom chord of the trusses. Or you can add "kickers" from gable wall to the roof deck. May be a little difficult to get between the webs of the trusses. Or run gable trusses full height (too late for that.)

 

[bagged89s10]

Once you put the ceiling in it will not shake if you cant do it now that's ok it is plenty strong with the roof sheathing if you still want to do something before you install the ceiling you can install 2x4 on the top of the bottom cord of the truss at a angle from the gables to the 35 foot walls make them as long as you can and if you need to use 2 2x4's you need to lap them next to each other by 2 trusses just not on one cord end to end. Another thing you can do is install plywood on the soffit before your soffit material of choice just remember to cut openings in it for venting if you are going to insulate and heat the building down the road this will add a extra horizontal brace to the 35 foot long wall

I think I’ll add some diagonals to the bottom chords and I’ll inspect how well the other braces are attached to the bottom chords before I insulate and drywall the ceiling.

 

[dave_dj1]

What does the plan and truss detail show? It should be all on there.

 

[mcbane]

I just had this 35x24 garage built. 10ft high walls and 24ft span trusses. yesterday I noticed if I grab the gable wall and try hard to shake it that I can shake the garage slightly. I think I need diagonal braces on the long 35ft wall and maybe one on each end of the wall with the doors The inspector didn’t say anything.

what should i use to add the braces? 1x4 on the face of the studs seems like the easiest? I do plan to insulate and drywall the garage so I would have to add a bunch of furring strips.

how long do I make them?

how many do I need?

which direction and angle is best?

thanks for your help.

I am an engineer but not in your state. Your observations sound like there was a snafu in construction, and you shouldn’t be doing as hoc corrective action based on details you get online. Contact the person who designed your structure and ask what details should have been constructed to resist side sway under design forces and also uplift during wind storms. Ideally ask that person to make a site visit so you can get clear corrective action items for your contractor.

 

[nadogail]

Without good bracing a building is like stack of dominoes; and I am not referring to pizza. Wind load and seismic activity have collapsed many buildings that somebody thought was "Good enough"

 

[lakeroadster]

I just had this 35x24 garage built. 10ft high walls and 24ft span trusses. yesterday I noticed if I grab the gable wall and try hard to shake it that I can shake the garage slightly. I think I need diagonal braces on the long 35ft wall and maybe one on each end of the wall with the doors The inspector didn’t say anything.

what should i use to add the braces? 1x4 on the face of the studs seems like the easiest? I do plan to insulate and drywall the garage so I would have to add a bunch of furring strips.

how long do I make them?

how many do I need?

which direction and angle is best?

thanks for your help.

That's an awesome building. I agree with @mcbane, get the Engineer who designed the building to come out and review the building verses the actual construction.

Food for thought: Any revisions you do on your own may end up biting you in the **** if there is ever an issue with the building. By making modifications, you may also be taking on the liability.

When I had my pole barn built I was on site during the entire construction. There were numerous items where the on site guys were not going to following the engineered drawings. Each time I pointed this out, showed them the drawing, and they then proceeded per the drawing.

 

[jonesg]

Once the vinyl siding is on it will lock everything in place.

 

[mrobins297aaa]

on the gable ends those studs need to be continuous from the floor plate to the bottom of what ever kind of truss you have there. if not you'll have a hinge joint at the top plate that you'll never get out with bracing.

 

[Stuart in MN]

If it is determined you need cross bracing on the walls, you can get formed metal bracing strips won't interfere with any interior sheathing: https://www.homedepot.com/p/Simpson...all-Bracing-with-Rolled-Edges-TWB12/100375133

 

[mike93lx]

Once the vinyl siding is on it will lock everything in place.

Ah yes, the elusive structural vinyl siding.

 

[Tracs]

Shouldn't the blocking in the stud cavities be positioned horizontal and not vertical?

 

[nmk_61802]

Shouldn't the blocking in the stud cavities be positioned horizontal and not vertical?

Don't think that is fire blocking, but code required nailers at each sheating seam. I believe either orientation is sufficient to comply with code.

 

[Toolfool]

Don't think that is fire blocking, but code required nailers at each sheating seam. I believe either orientation is sufficient to comply with code.

This is for shear. Hopefully, the framers have nailed off the plywood to these blocks as well as the studs.

 

[Tman]

If it is determined you need cross bracing on the walls, you can get formed metal bracing strips won't interfere with any interior sheathing: https://www.homedepot.com/p/Simpson...all-Bracing-with-Rolled-Edges-TWB12/100375133

I have used these a lot, they do their job.

If it is determined you need cross bracing on the walls, you can get formed metal bracing strips won't interfere with any interior sheathing: https://www.homedepot.com/p/Simpson...all-Bracing-with-Rolled-Edges-TWB12/100375133