BuickFarmer
Well-known member
What is standard for attaching the 2x12 truss carriers ie beams to the 6x6 poles. Will be using triple 2x6 laminated poles.
Attaching truss carriers to poles
- Thread starter BuickFarmer
- Start date
kd3pc
Well-known member
I always used though bolts, with 4x4" plates on each side
OP
BuickFarmer
Well-known member
I was considering four 10" X 1/2" or 3/8" carriage bolts with washers per post. Or would 2 do. Or would lag screws do? Neither the beams or pole will be treated so no need for galvanized, right?
Last edited:
tomroblee
Well-known member
When I was first thinking of building a pole barn (post frame building), I did some research. I ended up purchasing the NFBA (National Frame Builders Association) design manual. As I recall the manual specified the use of 1/2" or larger bolts for the connections. The number and size of the bolts depended on the load being placed on the connection. Heavy loads required shear plates (such as http://www.portlandbolt.com/products/others/shearplates.html) in addition to the bolts.
Over the years I have looked at the building codes for various cities and counties around the country. Most require through bolts for connections, but some allow the use of lag bolts. My rural property is located in SW Indiana where there are no building code or permit requirements. The standard practice there is to use large nails (spikes) for connections.
If you are building in an area subject to building codes you should consult with the proper authorities. If not, you might want to talk with someone in a nearby area that is subject to building codes.
Over the years I have looked at the building codes for various cities and counties around the country. Most require through bolts for connections, but some allow the use of lag bolts. My rural property is located in SW Indiana where there are no building code or permit requirements. The standard practice there is to use large nails (spikes) for connections.
If you are building in an area subject to building codes you should consult with the proper authorities. If not, you might want to talk with someone in a nearby area that is subject to building codes.
bczygan
Well-known member
Here's the free PDF file of the book:
http://jubilee101.com/subscription/pdf/Sheds-and-Barns/Barns---Post-Frame-Building-Design-Manual---105pages.pdf
theoldwizard1
Well-known member
What is the spacing of the posts (typically 8'), span (width) of the trusses and what type of roof ? If you are only 30' wide and a metal roof, doubled 2x8 would probably good enough.
I never heard of these before, but I would certainly want them IF the posts were NOT notched.
I am in favor of notching the post (i.e. cut out 2 of the 2x6 so that the carrier sits on top of them) and then through bolting (without shear plates).
tomroblee
Well-known member
My memory apparently isn't as good as it used to be (and probably never was.) When I skimmed the NPFA design manual again, I didn't see what I thought I remembered.
At the time I first considered building a post frame building (back in the late 1990's) I read several books on the subject. I do remember that connections suggested by the books far exceeded the actual construction practices that I observed in rural SW Indiana.
The examples that I have seen in recent years more commonly resemble:
http://www.pole-barn.info/truss-connection-details.html
I'm guessing that the "gold standard" varies by size of the building and the part of the country where it is being built, and the use of the building. The north may have heavier snow loads to contend with. The coastal areas may have stronger wind loads. A larger building may put more stress on individual connections. The harm from a failure will be much worse if the building is used for a school as oppose to being used to store hay.
At the time I first considered building a post frame building (back in the late 1990's) I read several books on the subject. I do remember that connections suggested by the books far exceeded the actual construction practices that I observed in rural SW Indiana.
The examples that I have seen in recent years more commonly resemble:
http://www.pole-barn.info/truss-connection-details.html
I'm guessing that the "gold standard" varies by size of the building and the part of the country where it is being built, and the use of the building. The north may have heavier snow loads to contend with. The coastal areas may have stronger wind loads. A larger building may put more stress on individual connections. The harm from a failure will be much worse if the building is used for a school as oppose to being used to store hay.
gayler
Well-known member
On mine the center laminated 2x6 is shorter so the truss sits between the outer two an is bolted together.
OP
BuickFarmer
Well-known member
Thanks everybody. And sorry, I should have given more info. The building will be 40X40x12 with 5/12 trusses on 4 ft centers toe nailed and hurricane strapped to truss carrier . 29 gauge metal roofing. Poles will be on 10' centers. Truss carriers will be 2x12 yellow pine on each side of a triple 2x6 laminated pole. On the exterior, I plan to nail a 2X6 on each post between the bottom of each 2x12 and the top of the top most 2x4 girt to provide additional support for that 2x12 carrier. On the interior the space between the poles will be filled with 2x6 studs on 2 ft centers and then horizontal 2x6's nailed to them from the floor to the bottom of the interior truss carrier as the interior wall covering.
Any recommendations on the drill bit for drilling 8 inches through yellow pine
Last edited:
theoldwizard1
Well-known member
Too much work !
from http://www.pole-barn.info/truss-connection-details.html
Pre-drill the post or the carrier on the ground with a guide. That way you know it will be square to the face of the board. Use a standard 1/2' twist drill, but slow down the speed.
Last edited:
ibedayank
Well-known member
metal trusses or wood?
OP
BuickFarmer
Well-known member
rburke65
Well-known member
What does your local county building permit office shave to say about this? If you do have a building Dept. that you have to satisfy.....
mrobins297aaa
Well-known member
here's a good way to attach the trusses to your 2x12's. you put a 2x6 between the 2x12's and let it extend up next to the top of the truss........gives a lot more nailing surface than those awful hurricane clips.
also when you lay out your poles and trusses make sure every other truss sets on top of a post (you did say your trusses are 4'-0 on center). cut the post off flush with your 2x12's and lay a 2x6 on the flat to fasten the truss to.
also when you lay out your poles and trusses make sure every other truss sets on top of a post (you did say your trusses are 4'-0 on center). cut the post off flush with your 2x12's and lay a 2x6 on the flat to fasten the truss to.
Last edited:
OP
BuickFarmer
Well-known member
here's a good way to attach the trusses to your 2x12's. you put a 2x6 between the 2x12's and let it extend up next to the top of the truss........gives a lot more nailing surface than those awful hurricane clips.
also when you lay out your poles and trusses make sure every other truss sets on top of a post (you did say your trusses are 4'-0 on center). cut the post off flush with your 2x12's and lay a 2x6 on the flat to fasten the truss to.
Thanks Mrobins, I had actually considered doing that with the 2x6's in between the 12's in addition to the hurricane clips on the inner 2x12. I've never used hurricane clips before, what do you find to be so awful about them? Since my posts are on 10' centers only one post will be conducive to tying onto the truss and I plan to leave that post high enough to be able to cut out and attach the truss to the actual post. I can't tell from the pictures what you used to connect your truss carrier to the pole with? What is the purpose of the 2x12 you have installed under the 2x12 truss carrier? What is the span of your trusses? Was it required for load bearing.
RBurke, my county requires permits for farm/pole barn buildings however they do not require plans nor inspections for anything other than electrical if you are having a new service line ran to it which I am. They are only interested in seeing the finished building for purposes of assessing value for taxes.
So my current plan in addition to what I described above is to pre-drill the outer 2x12, attach it and the inner 2x12 with only enough nails to hold them tight until I drill and install 4 1/2"X10" through bolts in each post, then add the remainder of the nails. Or I may even use 3.5 inch exterior screws. I feel comfortable that this will provide sufficient attachment relative to load bearing. Thanks everybody for you input.
Last edited:
mrobins297aaa
Well-known member
At my last house I had stud walls and the inspector made me use those hurricane clips at every truss and he insisted that every hole had to have a nail, well thats a lot of nails in a small area and it looks good on paper but it has a tendenacy to split the bottom the truss and actually make it weaker. when i got done with it i thought what a mess, whats stronger about that?........anyway just thoughts.
This barn I have at this place I had built (just getting to old I guest) when this inspector seen the way the trusses were done with the 2x6, he said "thats a hell of alot better than any hurricane clip"
I have a 36' span and my carriers are attached to the post with 20d galv twist nails at least 3 on each board. which is pretty much the norm for around here. Also my carriers are 2x10's 2 on the out side and one on the inside. i don't know why they did it that way maybe it was cheaper.
One of the things that this inspector wanted was any nails into the treated wood had to double dipped galv or stainless. when they showed up to erect the barn they were going to use regular 16d nails to fasten the 2x4 stringers to the post but i was ready for that and had purchased some 16d stainless nails for my framer and let them use that.
This barn I have at this place I had built (just getting to old I guest) when this inspector seen the way the trusses were done with the 2x6, he said "thats a hell of alot better than any hurricane clip"
I have a 36' span and my carriers are attached to the post with 20d galv twist nails at least 3 on each board. which is pretty much the norm for around here. Also my carriers are 2x10's 2 on the out side and one on the inside. i don't know why they did it that way maybe it was cheaper.
One of the things that this inspector wanted was any nails into the treated wood had to double dipped galv or stainless. when they showed up to erect the barn they were going to use regular 16d nails to fasten the 2x4 stringers to the post but i was ready for that and had purchased some 16d stainless nails for my framer and let them use that.
theoldwizard1
Well-known member
Simpson makes more than a dozen different types of "hurricane" truss connectors (their "H" series). Obviously you have to go with what the engineers specified or what the inspector approves. Some have a lot of holes, some don't. Pretty much all of them accept the Simpson Strong-Drive SD
Structural-Connector screws. Yes, they cost more than nails, but they are easy and quick to install.
mrobins297aaa
Well-known member
I probably didn't research it enough, I just used what homedepot had in stock at that time (which was what was shown in the previous post).
iirc (its been over 10 years) they had some special nails that went with them that i used...........I still like the 2x6 idea better, alot more surface area to spread out the nails.
OP
BuickFarmer
Well-known member
got the truss carriers up on one side today using 4 through bolts and about 20 nails per post. I used new 2x12 yellow pine on the outside of the post and salvaged 2x10's on the inside. The new 12's had bows in them, the salvage 10's were nice and straight. I will be using the 2x6's between them as you did which should help pull the bowed 12's in line, another benefit of the system you used.
mrobins297aaa
Well-known member
sounds like your making progress, hope you'll post some pic's when you get a chance.
it must be nice and warm down there by now, we just had our first nice day in the 50's up here in a while been a long winter.
it must be nice and warm down there by now, we just had our first nice day in the 50's up here in a while been a long winter.