Building your own trusses?

[HELLSUNICORN]

Anyone one ever build their own pole barn roof trusses? I need some soon but the truss builders are telling me at least 9-12 days to have them built. I am putting an addition on my building and need 5 of them. If I build them I plan on copying what I have because they will have the exact same span and needs as the old trusses.

Any one have input on this? Am I going to kill a bus load of nuns if I attempt it?

Thanks

 

[jkwilson]

The joints are really hard to secure on your own. Those plates don't look like much, but the are really strong connections.

 

[Kev442]

You won't have much luck with the metal joints they use, they are applied under tons of pressure. The homemade way is too use plywood gussets with a strong adhesive, twist nails and screws.

 

[Thumper68]

I have built quite a few copying existing ones, I use Liquid nails and OSB or plywood for the joints. Make sure to give the construction adhesive a day or two to set before adding weight and use plenty of nails. Best if you can make a jig to hold the pieces in place as they are assembled.

Also I make sure to use straight grain doug fir for the bottom cord.

 

[Kev442]

I was told if I used OSB, it would be an automatic inspection fail.

 

[stafford]

how wide is your building? I've built a bunch of trusses but none any bigger than 26' that I remember. Like mentioned earlier use 1/2" plywood or osb and nail the piss out of them using 6 penny CC's. they won't come out the back side like 8 penny cc's would. saving you from having to bend them down flat. I've never used any liquid nails on any of them but it's not a bad idea. if it's only 9 to 12 days that's not that long to wait. it'll take you longer than you might think to build them.
Good luck. what ever you decide to do.
Stafford

 

[A_Pmech]

You can make a plate press from a bottle jack and scrap if so inclined. I prefer Teco ring connectors, however.

 

[nicksL98]

You'll waste more time trying to make them than its worth, especially if its over 15'wide. By the time you're finished your new trusses would already be waiting for you.

 

[HELLSUNICORN]

The trusses are very basic 20 feet wide with a 4-12 pitch. I am going to buy a 20' 2x8 for the bottom, 2x6s for the top and the center gussets are 2x4. I planned on using plywood gussets nailed and glued in the center and metal plates on the end. I am going to make my own plates out of 16 gauge. Drilling about a million holes and nailing through them. I have to use metal on the ends because of the need to **** up against the pole.

I figure once I get the boards cut and a jig made on the floor I should be able to knock them out in a couple of hours with the help of some friends.

This is the weekend its going up so I need them now. Between my work schedule and the schedules of the people helping me its kind of a last minute deal.

Thanks for the input I appreciate it.

 

[Mr_fixit]

I made some trusses for a shed using a 30 ton press & press plates. I would suggest you wait for the professionally built ones. I made up a jig on the floor, too.

 

[brass89]

Trusses aren't so bad when you have the right equipment. I'm sure a beefy press of sorts would work but no idea how long it would take. I've seen some press plates sold in big box stores but as I recall they aren't the same as the ones used in truss plants. They definitely don't just hammer in. Used to use hydraulic presses ranging from 8,000 - 15,000 psi to set them. Personally I wouldn't trust osb/plywood gussets with adhesive and nails or screws on a larger truss. On a smaller shed it's a different story. The dimensions and thickness of the plates (some are plain steel, some are green painted etc) are called for by engineering specs from an architect for a specific job. Even though they're thin, the metal plates pressed evenly together to form a nice even 'sandwich' creates a helluva bond and the steel resists more bending compressions with the truss in an upright position than any pieces of sheathing.

I've got a feeling you might be better off waiting the few extra days. If your luck is anything like mine, just about the time you finish cussing the last one the place would call and tell you they're built. Even using raised metal tables with magnetic locking bases, adjustable stops etc, 4-5 man crew in an environment made for truss building.. setup would take anywhere from 25-40min. Depending what headaches we ran into and some of the boards would refuse to fit perfectly so had to be readjusted midway through anyway.

Best of luck if you choose to tackle it.

 

[Nowater]

Not legal around here.

 

[Orange65]

If the building requires inspection, the inspector may require stamped plans for the trusses. That happened to a buddy of mine- cost him $1000 to get the plans stamped.

 

[ez-duzit]

The building inspector will never approve home-made trusses.

 

[Imcrazy]

I built ones for a 20 X 30 Pole Barn years ago. The plans they sent with the kit showed that i needed a bunch of scaffolding which I couldnt afford.

I lined it all out on a flat part of the driveway with a tape and a chalk box. Cut them out and gussetted them with plywood.

This was in the country and no inspection required. The barn is still standing.

 

[rancherbill]

...I need some soon but the truss builders are telling me at least 9-12 days to have them built....

This is called an unforeseen construction delay. Wait to get factory ones.

If you need to get it done quickly, use old style rafter construction plans and techniques.

 

[dutchgray]

This is called an unforeseen construction delay. Wait to get factory ones.

If you need to get it done quickly, use old style rafter construction plans and techniques.

Which makes a far better roof IMO, but in 10 years in construction I have yet to use a truss, everything I have done has been cut, but then we are old fashioned at our firm.

 

[John in OH]

As others have mentioned already, if an inspection is required, home-made trusses may be a problem. Those press-plate connections look kind of goofy, but they are engineered connectors with specific design capabilities, strength characteristics, and proven performance.

Sure, you can cut lumber to match the pieces in the existing trusses, but what you will be missing is any "proof" that your plywood reinforced, glued and nailed connections are equal to the press plate joints.

You don't list a location in your profile, but unless you are really out in the boonies, there should be multiple sources of pre-fab trusses within a reasonable drive.

 

[whyNick?]

I built ones for a 20 X 30 Pole Barn years ago. The plans they sent with the kit showed that i needed a bunch of scaffolding which I couldnt afford.

I lined it all out on a flat part of the driveway with a tape and a chalk box. Cut them out and gussetted them with plywood.

This was in the country and no inspection required. The barn is still standing.

Ditto, I made my own using this method on my 24x32 back in 2000, it is still standing and the roof is arrow straight. No inspection required however...

 

[finn]

I live in the Boonies, and the Inspector won't accept home-made trusses here, either.

 

[A_Pmech]

I live in the Boonies, and the Inspector won't accept home-made trusses here, either.

You're not far enough out in the boonies then!

 

[sublime68charger]

I gonna say you can build your own but I'm just a hack with a hammer

If you click on my yea old garage thread you can see my home made 2nd hand trusses.

My trusses are 24' wide and had just a single support in the middle I added a 2x4 to each side been fine for me.

As long as you follow the same design as what you had and use plywood or metal as the gusset plates you be fine. And use both screws and nails. Nails for the sheer strength and screws to hold the plate tight to the boards.

Just my thoughts

 

[dogdas]

Anyone one ever build their own pole barn roof trusses? I need some soon but the truss builders are telling me at least 9-12 days to have them built. I am putting an addition on my building and need 5 of them. If I build them I plan on copying what I have because they will have the exact same span and needs as the old trusses.

Any one have input on this? Am I going to kill a bus load of nuns if I attempt it?

Thanks

9-12 days and you're sad? I waited 5 weeks here in Michigan. How long is it going to take you to build the trusses? 3-4 days maybe more maybe less. Wait the 9 days and have engineered drawings to back you up. If you make them and by a million to one chance something happened that would give your insurance company some footing to deny your claim. Did I mention liability?

 

[sublime68charger]

The trusses are very basic 20 feet wide with a 4-12 pitch. I am going to buy a 20' 2x8 for the bottom, 2x6s for the top and the center gussets are 2x4. I planned on using plywood gussets nailed and glued in the center and metal plates on the end. I am going to make my own plates out of 16 gauge. Drilling about a million holes and nailing through them. I have to use metal on the ends because of the need to **** up against the pole.

I figure once I get the boards cut and a jig made on the floor I should be able to knock them out in a couple of hours with the help of some friends.

This is the weekend its going up so I need them now. Between my work schedule and the schedules of the people helping me its kind of a last minute deal.

Thanks for the input I appreciate it.

If it was me I'd run a 2x 6 for the center support.

Any chance of getting a pic of your old truss set up

 

[kbs2244]

This is a true local inspector question.
I was on the side involved with a small church add on.
They just wanted to extend the existing auditorium 30 feet.
The original building was built with factory trusses.
With out asking they built the addition with homemade, but matching trusses.
They used plywood gussets with screws instead of the gang nails at the joints.
Both sides.
The inspector was concerned about the kind of glue used.
But when shown the empty glue tubes used, he passed it.

 

[C96]

Not worth the risk in my opinion, you need the documentation from the truss company.

Seriously, how much time are you really going to save especially if it gets turned down?

 

[carcajou]

I always build my own. PM me for any info you need. I just put up these last month.

 

[John in OH]

After re-reading this thread this morning, I had an additional thought.

You actually have two potential problems here ... 1) Will your plywood/glue/nailed connectors be adequate; and 2) Will the inspector accept the home-made trusses?

Some years ago, IIRC, I came across several websites from universities and/or the US Dept of Agriculture that had FREE engineered plans for pole barns for agricultural uses. Part of these plans included details for trusses and truss connectors fabricated from plywood/glue/nails. These connectors had been engineered by the appropriate engineering departments of the universities and the plans specified plywood connector size, type of glue and application, and number and location of nails, etc.

If you can find one or two of these sites, suggest you download the appropriate drawing/s and show them to your inspector BEFORE you fab the trusses and see if he will accept them.

 

[srmofo]

Which makes a far better roof IMO, but in 10 years in construction I have yet to use a truss, everything I have done has been cut, but then we are old fashioned at our firm.

Just curious what characteristics you consider better? What FEA have you done comparing the 2?

 

[kbs2244]

My favorite site for DIY auxiliary buildings is:

http://www.ag.ndsu.edu/extension-aben/buildingplans

For all things pole construction related:

http://www.pole-barn.info/pole-building-construction.html
(Do the top line download. It is worth the time.)

For free truss plans:
http://www.public.iastate.edu/~mwps_dis/mwps_web/tr_plans.html

 

[dutchgray]

Just curious what characteristics you consider better? What FEA have you done comparing the 2?

I don't do calculations, I just build what's on the plan, the timber is specified from a set of tables to be adequate, for instance the last roof I did was a small extension hipped on to existing, 16' span 25 degree pitch, used 6" by 2" rafters and ceiling collars at 16" centers with 8" by 2" ridge, which is much more than trusses would be and you get a clear loft you can actually get in. Its just traditional methods but with bigger wood than in the past because the quality is so low nowadays. We do a lot of dormers, hips and valleys and also differing pitches between them and once you start doing that you may as well do it all yourself. The last big roof I did was at 48 degrees and had 16 thousand plain tiles on it, that one was hell to do.
Trusses are the standard roof on the normal mass built house and have been for 40 plus years, but that's not the type of work I do. I know of plenty truss roofs that have failed over the years, most of which were done right but the truss design was not up to it, they are stronger now than in the past, but it goes to show engineers get it wrong sometimes

 

[Iowa Mark]

With a 20' span and a 2x8 lower cord you almost have all the strength without any trussing above. The price of the lumber is going to be more than a standard factory built 2x4 truss with almost 0 deflection across that 20 feet. As has been stated before, there are many plans online with enough stress calculations and fastener specs to bury any building inspector, if you go ahead with building your own.

 

[ms fowler]

In my experience, OSB is a no-no. I have worked for a number of engineers and I do the field work. The Engineer never allows OSB.

Truss failures are most often due to failure to properly brace the bottom chord, assuming trusses were installed plumb. . IIRC, the Truss Plate Institute requires lateral bracing of the bottom chord at no more than 10' OC. Usually if you locate the lateral braces at near the factory connection points as possible, you will be fine. ( The difference in stiffness between braced and unbraced trusses is amazing).

 

[Elmo4895]

If you use plywood plates make them at least 14" tall and 16" long and glue to the edges. Also use a triangle nailing pattern, it is much more rigid.