Pole Barn Gable End Framing

[Not db4600]

Well, after six months I finally have a roof on my metal truss pole barn. First crew abandoned me after sitting the posts. Numerous calls and texts went unanswered. I found another crew building one near me and I went and asked if they would finish mine. They did after I purchased the rest of the needed
2x6 purlins and metal for the roof.
I finished the side that most of my rain comes from but want to close in the front gable end. I was reading where they say NOT to connect your gable end
framing to the truss. They said it should be connected to the purlins and not the truss. Not sure I understand that but don't want to do it wrong. I was wondering if anyone knows how to properly do this. I have searched the web and can't find any good info.
I plan to enclose the gable end from top to ground and have two sliding doors to help keep prying eyes out. lololol
Any advice is appreciated.
Tom

Purple you have done nothing more than ask advice, but maybe at the wrong place. You’ve done nothing wrong and you are getting chastised.
If it were mine I would tip poles or studs or panels next to those end trusses and use a bolted angle connection. Usually a connection point within 3-4” of the panel point is recommended. I can say 35 years experience in building had some merit, but it don’t mean squat here. I will agree that a 2x6 diagonal brace in the four corners of the eave walls would make me sleep better.

The fact that there are integral tabs for roof purlins and bottom chord braces has some merit that the truss supplier has put a pencil to paper.

 

[Scott 730]

I do see some kind of gable braces in your picture?

The picture is not from the OP's building. It is just a picture for reference, as he stated.

 

[Not db4600]

So... are you buying discrete parts, like rafters, poles, purlins and such... and designing a building out of them on the fly?

I ask, because the trusses may be designed to handle 140mph winds... but their connections to the poles may not... if you came up with your own connection method. (this may be fine... I'm just picking on one aspect of the design)

If the entire building isn't built from a kit of parts designed to go together to meet their specs... connected together according to an planned design...then what guarantees that any of the individual parts will live up to their specs?

Anyway...

I'm not going to tell you what to do... but I'm going to do two things.

1. Say that a building is a system. The truss may be able to take 140mph wind and maintain its shape; but if you find it in pristine condition... one county over, because it detached from the rest of the building... doesn't do much good.

2. I'm assuming that the wind load on the truss that its rated for would be blowing from right to left... or left to right in your pictures. The truss rating (I don't think) doesn't say anything about how much wind it can withstand, while trying to hold ... essentially a sail... (the end of your barn) against the wind.

Bonus... I guess I'm doing three things...here is a video of a local roof collapse from snow loading. Yeah... I know it's snow... not wind...

But watch the second take of the video in slow motion. The trusses were fine with the snow... but the building had a crappy connection between the gable end and the trusses... calamity ensued.

Without knowing how strong your gable end itself is... does it have poles? How strong is the header? Is there any other bracing from the gable header to the truss system?... I'm not sure anybody can say how to meet your design goals by connection to the trusses alone...

The building is a system...and it's only as strong as its weakest link...

UPDATED: Barneveld Fire House Collapses; No Injuries Reported

Another building has fallen victim to heavy snow.

www.wktv.com

I’m gonna guess Purple’s Florida snow melts faster then Sheboygan’s.

Where’s the proof that the gable to truss connection of the Barneveld building failed before the rest of the roof? The second slow motion run of the video has movement at the eave soffit before the gable end moves. I know nothing of the Barneveld structure. What was the span, the frequency, and were the trusses single or laminated? How were they braced? Were there intermediate walls. What was the ceiling load?

 

[Janicholson]

Purple you have done nothing more than ask advice, but maybe at the wrong place. You’ve done nothing wrong and you are getting chastised.
If it were mine I would tip poles or studs or panels next to those end trusses and use a bolted angle connection. Usually a connection point within 3-4” of the panel point is recommended. I can say 35 years experience in building had some merit, but it don’t mean squat here. I will agree that a 2x6 diagonal brace in the four corners of the eave walls would make me sleep better.

The fact that there are integral tabs for roof purlins and bottom chord braces has some merit that the truss supplier has put a pencil to paper.

I agree. I also believe that High force winds can come from all directions (even in the same storm. I would not leave a open side there. Jim

 

[john in la]

I have those type trusses.
While they will not stand up to snow load they work well in the deep south wind loads.
In fact I bet 99% of the answers here questioning these trusses have never seen never alone worked with these trusses.

If you want to build gable end walls support the walls with post.
Just do not hang gable end enclosures like in the picture off the trusses.
They can not hold the extra weight or wind load.
They make special gable end trusses that will hold the weight if you wanted this.

The biggest part of adding walls to a pole barn is bracing because now the wind has a flat surface to push against.
Take some 2x4s and nail X bracing to the bottom of your roof purlins and a couple sheets of plywood or OSB in each wall corner is the best bracing for the money you can buy.

 

[caterpillar guy]

I would start by contacting the truss manufacturer, to see about some bracing to the trusses corner ways. Even send them a couple pictures and make them such that the walls don't look like they are sloping inward at the bottom like they do in these pictures you show here. Then see what they use for the bracing be it rod or cable even chain going from one truss to the other making an X between each truss on the ends so the roof is braced endways. This needs to be on each sloping side of the truss. and at both ends. Then find out what is used for bracing from the walls to the trusses for bracing so the walls hold steady without tipping over sideways. After this is accomplished then you can put a wall in on an end .While talking to them about the bracing ask about the end walls and how they connect a wall with a sliding door in the mix. I know what I would do but ours are built from home sawn material with rough cut lumber and all home built pieces including the trusses all wood. Some of them are close to 60years old and the last one was built in the 80's so all of 40 years old and all still standing with no issues of holding in storms . Tough we don't see sustained winds of the velocity you have in FL with hurricanes. We do have snow load which can be just as devastating as wind. Now I would gt my bracing in first. With som long 2x4or 6's between the posts from top of one post to bottom of the next and then do the same at the other end such the top outer end post is fastened at the top to the bottom of the second post this will help support against posts moving in the ground. Then those trusses need the bracing as soon as you can. I've seen these style trusses used in many places from KS to TX and further west and east with apparently little trouble with them. I believe the trusses will carry the load pretty well just need that bracing on them from top end of one truss to bottom of the next one diagonally then making a cross or X in the opposite on the same truss. then on the opposite side do the same thing and go to the other end and repeat on both slopes. This will solve the shifting of the trusses sideways you will need to account for pulling as you tighten the X bracing so it is tight and not distorting the trusses since the roofing is already on it. Probably also needs to be on the top chord of the truss. so will need to thread it through the trusses inline with the second attaching point. IF cable a long turn buckle will help with final tightening if rod then long threads on each end so it can be taken up tight. IF chain either one would work as long as you can get it tight. Chain would probably want to be at least 5/16ths and cable 3/8 rod in the 3/8-1/2 inch would work . I would probably opt for the heavier of all choices just me. I have thought about a truss something like those for here with an insulation on the bottom of the truss for heating it. once all bracing is in then worry about what walls you want and how. Mostly see trusses like the one shown in John's picture or all steel buildings. If you want the side open then you will need to see about some short bracing in that wall for being able to get in and out with what ever you want to get through the opening with. If just doors on the end with both sides enclosed it would taks some other plans like a couple posts in to the top of the trusses to hold the header for the door and track. With the bracing in I would not see why one could not attach the 2 posts to the top of the truss since it is not a load bearing item just a support for the top of the post and would help with truss end movement some. Especially if they were spaced such that they are evenly set along the wall so the door would be centered on the end wall leaving some space along both sides. Thus making it easier to enclose the wall with o need of more posts. IF 40 Ft wide and a 24or 30 ft door were used you would only need about 10-16 ft ft left to enclose so no need for more posts just fasten your girts to the posts and corner post and side up. Put coner piece on and done both sides. Yes if you put a 24or 30 ft door in you will need to either put a track support out beyond the wall to hold it or use 2 over lapping doors which can be slid by each other with a double track and doors . But still start with the manufacturer first for their information on this.

 

[will-max dairy]

I’m gonna guess Purple’s Florida snow melts faster then Sheboygan’s.

Where’s the proof that the gable to truss connection of the Barneveld building failed before the rest of the roof? The second slow motion run of the video has movement at the eave soffit before the gable end moves. I know nothing of the Barneveld structure. What was the span, the frequency, and were the trusses single or laminated? How were they braced? Were there intermediate walls. What was the ceiling load?

All I'm saying is... the front wall buckled out and the trusses essentially fell like dominos, as opposed to caving in.

And sure, there is no snow (or little) snow load where this building is.

The video is an example of how failures aren't always vertical, nothing more.

Someone came here asking essentially an architectural question that rigorously would require a Civil Engineer. I'm no Civil Engineer. There may be some here; but even they can't (and shouldn't) do a quantitative analysis based on the information given.

So... I provided an example of how a building can fail... and leave it to the motivated reader as to how they want to prevent it.

 

[purplewg]

The building in this picture has X braces between trusses that I don't see in your first 2 pictures.

Yeah, X bracing is not required in FL. We have engineered trusses that are a bit more durable.

 

[will-max dairy]

I hope my post wasn't taken as "chastising"... I've done plenty of cowboy engineering in my day.

What's already built looks strong. All I'm saying is that an end wall is just a big old buff body facing the wind. A friend of ours built a 80x200 coverall for his cows. The coverall trusses are very strong. They've never so much as twitched in all of the years that it's been standing.

But, it was open ended... and drafty in the winter... so he put an end on it...with no more vertical posts or proper bracing...

The end was summarily blown in during the next wind storm. The trusses and main structure are fine and still standing. And... in my layman's opinion... I've seen some snow load roof failures around here that are more of a truss domino thingy... or gable end blowouts...than an actual truss cave-in

So... it can happen...

But...I'm sure that you can put on a gable end with some common sense bracing...

What that is, is kinda left up to you, as the "on site engineer..." Seems like there's already been some good advice.


And.. full disclosure... I was thinking about this thread when I went into the hayloft to get hay this morning... in our 150 year old post-n-beam bank barn. I kinda chuckled, because it's built like a tank... but I usually leave a few tiers of hay in the ends for just this reason... the ends "breathe" back and forth in the wind a little. It stood up to all the snow we had last winter... but a 140mph straight line wind would probably reduce it to a heap...

 

[purplewg]

So... are you buying discrete parts, like rafters, poles, purlins and such... and designing a building out of them on the fly?

I ask, because the trusses may be designed to handle 140mph winds... but their connections to the poles may not... if you came up with your own connection method. (this may be fine... I'm just picking on one aspect of the design)

If the entire building isn't built from a kit of parts designed to go together to meet their specs... connected together according to an planned design...then what guarantees that any of the individual parts will live up to their specs?

Anyway...

I'm not going to tell you what to do... but I'm going to do two things.

1. Say that a building is a system. The truss may be able to take 140mph wind and maintain its shape; but if you find it in pristine condition... one county over, because it detached from the rest of the building... doesn't do much good.

2. I'm assuming that the wind load on the truss that its rated for would be blowing from right to left... or left to right in your pictures. The truss rating (I don't think) doesn't say anything about how much wind it can withstand, while trying to hold ... essentially a sail... (the end of your barn) against the wind.

Bonus... I guess I'm doing three things...here is a video of a local roof collapse from snow loading. Yeah... I know it's snow... not wind...

But watch the second take of the video in slow motion. The trusses were fine with the snow... but the building had a crappy connection between the gable end and the trusses... calamity ensued.

Without knowing how strong your gable end itself is... does it have poles? How strong is the header? Is there any other bracing from the gable header to the truss system?... I'm not sure anybody can say how to meet your design goals by connection to the trusses alone...

The building is a system...and it's only as strong as its weakest link...

UPDATED: Barneveld Fire House Collapses; No Injuries Reported

Another building has fallen victim to heavy snow.

www.wktv.com

To your first question. No, it was an engineered system based on Fl requirements. The original outfit designed the post/truss structure based on FL requirements. I ended up buying the metal and 2x6's separate because they never returned.
Yes, I will have two 8x8 posts verticle to the gable ends. One end will be just to support the open end so I can put my cow fence back up. The other end will support two sliding doors. The header I plan to us is pre-engineered laminated 2x10's.
There is nothing that will stand up to a micro burst or a tornado. This barn I suspect will be 10x more likely to stand up in a hurricane than the one I tore down to make room for this one. lol That said, in the last five years the old barn went through at least 5 hurricanes with no issues. I did
lose a piece of metal on occasion.

 

[purplewg]

Doesn't sound complicated to me. Not sure how they set the gable end trusses but they should have offset the gable end truss for you to be able to frame up to the purlins.

Vito

Yeah, the gable end over hangs are about 18 inches. The crew that I had finish the roof system were very good. I am actually going to go see a barn they installed near me soon that has one open end and a closed end with sliding doors. It will should show me what I need to do to do the same setup.

 

[purplewg]

You might be able to save it if you run some knee braces from every rafter down to every post. Then run some cable X in the walls.

Yeah, I thought about the knee braces and probably will do that. I plan to use 2x6 X bracing on the side walls.

 

[purplewg]

I think you're going to have to set at least two poles on the gable ends, one on each side of the door opening. On a building that size you can't just have a floating curtain wall hanging from the purlins.

I agree. I just received four 8x8x20 posts yesterday for the gable end supports.

 

[purplewg]

Purple you have done nothing more than ask advice, but maybe at the wrong place. You’ve done nothing wrong and you are getting chastised.
If it were mine I would tip poles or studs or panels next to those end trusses and use a bolted angle connection. Usually a connection point within 3-4” of the panel point is recommended. I can say 35 years experience in building had some merit, but it don’t mean squat here. I will agree that a 2x6 diagonal brace in the four corners of the eave walls would make me sleep better.

The fact that there are integral tabs for roof purlins and bottom chord braces has some merit that the truss supplier has put a pencil to paper.

Thanks db4600. Yeah, I have only seen a couple of posts that pertain to my original question but I appreciate the input. Many of the ideas people have thrown out here I had already planned on doing. X-bracing the walls, knee braces on the trusses, pre-engineered header for the sliding doors and such. I do have some experience building. I built both of my last two houses and both passed inspection the first time. This is a barn though and not a home so things can be a bit different.

 

[purplewg]

I have those type trusses.
While they will not stand up to snow load they work well in the deep south wind loads.
In fact I bet 99% of the answers here questioning these trusses have never seen never alone worked with these trusses.

If you want to build gable end walls support the walls with post.
Just do not hang gable end enclosures like in the picture off the trusses.
They can not hold the extra weight or wind load.
They make special gable end trusses that will hold the weight if you wanted this.

The biggest part of adding walls to a pole barn is bracing because now the wind has a flat surface to push against.
Take some 2x4s and nail X bracing to the bottom of your roof purlins and a couple sheets of plywood or OSB in each wall corner is the best bracing for the money you can buy.

Good ideas and thanks. Yeah, I saw a picture of a barn like mine that survived a direct hurricane hit on the west coast in 2024. Everything around it was leveled but the barn was standing like it had just been put up. These things need to be able to flex somewhat. I think that is why my 60 some year old barn stood through so many hurricanes.

 

[purplewg]

I would start by contacting the truss manufacturer, to see about some bracing to the trusses corner ways. Even send them a couple pictures and make them such that the walls don't look like they are sloping inward at the bottom like they do in these pictures you show here. Then see what they use for the bracing be it rod or cable even chain going from one truss to the other making an X between each truss on the ends so the roof is braced endways. This needs to be on each sloping side of the truss. and at both ends. Then find out what is used for bracing from the walls to the trusses for bracing so the walls hold steady without tipping over sideways. After this is accomplished then you can put a wall in on an end .While talking to them about the bracing ask about the end walls and how they connect a wall with a sliding door in the mix. I know what I would do but ours are built from home sawn material with rough cut lumber and all home built pieces including the trusses all wood. Some of them are close to 60years old and the last one was built in the 80's so all of 40 years old and all still standing with no issues of holding in storms . Tough we don't see sustained winds of the velocity you have in FL with hurricanes. We do have snow load which can be just as devastating as wind. Now I would gt my bracing in first. With som long 2x4or 6's between the posts from top of one post to bottom of the next and then do the same at the other end such the top outer end post is fastened at the top to the bottom of the second post this will help support against posts moving in the ground. Then those trusses need the bracing as soon as you can. I've seen these style trusses used in many places from KS to TX and further west and east with apparently little trouble with them. I believe the trusses will carry the load pretty well just need that bracing on them from top end of one truss to bottom of the next one diagonally then making a cross or X in the opposite on the same truss. then on the opposite side do the same thing and go to the other end and repeat on both slopes. This will solve the shifting of the trusses sideways you will need to account for pulling as you tighten the X bracing so it is tight and not distorting the trusses since the roofing is already on it. Probably also needs to be on the top chord of the truss. so will need to thread it through the trusses inline with the second attaching point. IF cable a long turn buckle will help with final tightening if rod then long threads on each end so it can be taken up tight. IF chain either one would work as long as you can get it tight. Chain would probably want to be at least 5/16ths and cable 3/8 rod in the 3/8-1/2 inch would work . I would probably opt for the heavier of all choices just me. I have thought about a truss something like those for here with an insulation on the bottom of the truss for heating it. once all bracing is in then worry about what walls you want and how. Mostly see trusses like the one shown in John's picture or all steel buildings. If you want the side open then you will need to see about some short bracing in that wall for being able to get in and out with what ever you want to get through the opening with. If just doors on the end with both sides enclosed it would taks some other plans like a couple posts in to the top of the trusses to hold the header for the door and track. With the bracing in I would not see why one could not attach the 2 posts to the top of the truss since it is not a load bearing item just a support for the top of the post and would help with truss end movement some. Especially if they were spaced such that they are evenly set along the wall so the door would be centered on the end wall leaving some space along both sides. Thus making it easier to enclose the wall with o need of more posts. IF 40 Ft wide and a 24or 30 ft door were used you would only need about 10-16 ft ft left to enclose so no need for more posts just fasten your girts to the posts and corner post and side up. Put coner piece on and done both sides. Yes if you put a 24or 30 ft door in you will need to either put a track support out beyond the wall to hold it or use 2 over lapping doors which can be slid by each other with a double track and doors . But still start with the manufacturer first for their information on this.

Thanks Cat guy. All very good ideas. I bascially will end up build an end truss out of wood. I was more curious as to the logic of not attaching the two posts for my sliding doors and headers to the existing metal truss on the gable end. I think I read somewhere where they mentioned constant flexing from wind on the gable end eventually cracking the metal truss if attached.

 

[will-max dairy]

Thanks Cat guy. All very good ideas. I bascially will end up build an end truss out of wood. I was more curious as to the logic of not attaching the two posts for my sliding doors and headers to the existing metal truss on the gable end. I think I read somewhere where they mentioned constant flexing from wind on the gable end eventually cracking the metal truss if attached.

That... is a nuance that I never thought of...

There is a rabbit hole on the internet about the notion of "fatigue limit"... as in, there is a certain amount of flex that wouldn't induce a crack, no matter how many cycles you endure...

I wonder how much flex a truss can endure per cycle while staying under the "fatigue limit"...

(also... I'm just thinking out loud here... I honestly don't think this helps you lol... other than to say... it's quite a nuance...)

 

[will-max dairy]

Thanks Cat guy. All very good ideas. I bascially will end up build an end truss out of wood. I was more curious as to the logic of not attaching the two posts for my sliding doors and headers to the existing metal truss on the gable end. I think I read somewhere where they mentioned constant flexing from wind on the gable end eventually cracking the metal truss if attached.

But that also lends some logic to the notion of bracing to the purlins... because... a diagonal brace from the gable header up to the purlins would translate a horizontal flex in the gable end to a vertical flex on the truss system... and a horizontal force on the purlin system... sorta dissipating the flex into the whole structure, as opposed to making the bottom edge of one truss take it all...

I'm kinda starting to smell what you're steppin' in here... lol...

 

[purplewg]

I hope my post wasn't taken as "chastising"... I've done plenty of cowboy engineering in my day.

What's already built looks strong. All I'm saying is that an end wall is just a big old buff body facing the wind. A friend of ours built a 80x200 coverall for his cows. The coverall trusses are very strong. They've never so much as twitched in all of the years that it's been standing.

But, it was open ended... and drafty in the winter... so he put an end on it...with no more vertical posts or proper bracing...

The end was summarily blown in during the next wind storm. The trusses and main structure are fine and still standing. And... in my layman's opinion... I've seen some snow load roof failures around here that are more of a truss domino thingy... or gable end blowouts...than an actual truss cave-in

So... it can happen...

But...I'm sure that you can put on a gable end with some common sense bracing...

What that is, is kinda left up to you, as the "on site engineer..." Seems like there's already been some good advice.


And.. full disclosure... I was thinking about this thread when I went into the hayloft to get hay this morning... in our 150 year old post-n-beam bank barn. I kinda chuckled, because it's built like a tank... but I usually leave a few tiers of hay in the ends for just this reason... the ends "breathe" back and forth in the wind a little. It stood up to all the snow we had last winter... but a 140mph straight line wind would probably reduce it to a heap...

No problem Will. I received a lot of advice on bracing which I had planned on doing anyway. I was more curious as to my original question of
attaching my vertical posts on the gable ends to the metal trusses. Right or wrong? lol I still plan to go look at a neighbors barn that was built by the team that finished my roofing. They work for one company here and do all their work. They came and spent two days on a weekend to finish my roof. I was impressed with them. The original guys had the barn 6 inches out of square and I told the last team about it. I was impressed with how they were able to square my roof even though the posts were out of square. No stair stepping on the metal anywhere. Now, I wouldn't even think about it if I hadn't checked squareness of the posts myself while waiting to get the roof structure done.

 

[purplewg]

But that also lends some logic to the notion of bracing to the purlins... because... a diagonal brace from the gable header up to the purlins would translate a horizontal flex in the gable end to a vertical flex on the truss system... and a horizontal force on the purlin system... sorta dissipating the flex into the whole structure, as opposed to making the bottom edge of one truss take it all...

I'm kinda starting to smell what you're steppin' in here... lol...

Will, I don't plan on attaching gable end bracing to the truss at all. Those diagonal braces will go up to the purlins.