Do It Yourself wooden trusses

[skid mark]

Have been pouring over all of the great info on this site for weeks, gathering info, saving my pennies and starting to put together plans for a new barn.

Am thinking of a plain pole barn with dirt floor now, slab, insulation, elec, etc later. Clear span roof trusses are certainly appealing!

I really like the do it yourself approach as my finances are limited. I've built a couple steel framed barns in the past but I'm leaning towards wood this round as I believe that they are easier to insulate.

I made a note of this site that has lots of free plans available for download. Thanks to whoever posted the URL for this web page!

I looked over all of the wooden truss plans that were sized to fit my needs. Most used plywood gussets at the joints for the trusses. The thing that I didn't care for about using plywood gussets is that they require lots of nails to handle the forces and cutting out the gusset plates would take quite a bit of time. In addition to taking lots of time to drive, I get nervous putting too many nails in a small area. In the middle of the night I'd be listening for the wood to split under a heavy load! /forums/images/graemlins/smile.gif

On the other hand, this set of plans uses split ring connectors instead of gusset plates.

So each joint would simply have two or more 2xX's overlapping, with a ring connector in between and a single 1/2" bolt through the center to hold the sandwich together. In my opinion, this would be quite a bit less work than cutting a pair of gusset plates and driving 20-30 nails per joint!

I like that idea!

The only nit about putting in a split ring connector is that you have to drill a 3/8" circular groove (like a hole saw would cut) in the pieces to be joined. The connector sits in this groove. So this is a little bit of work and also the groove reduces the cross section of the 2xX (which I'm confident that the plans take into account).

One other shear developer in the same family as the split ring connector is the spike grid.

This beauty is kind of like a toothed mending plate that sits between instead of outside a joint as do the plates the big guys use to put together lightweight wood trusses. And unlike the later, the spike grid can be installed by you and I with no special tools. Put it in place, tighten the bolt and the teeth are forced into the members being joined. And the spike grid does not reduce the cross section of the members being joined. Another plus!

Also I would bet that the spike grid would do a better job of holding the joint rigid around the Z axis than would a split ring connector where the two members could possibly rotate around the connector.

Has anybody had any experience with either of these connectors? They sure look like a lot less hassle than home made plywood gusset plates.

Fun stuff!

Mark

 

[BobReeves]

I have no experience with either but I would think the choice would depend on what tools are available and your perception of what would be easier for you to do. Personally I would probably do the plywood, sounds less of a hassle to align and put together..

I have a real nice table saw, radial arm saw and chop saw, once I had the saws set up cutting the plywood gussets would be a piece of cake. I also have a 1/2" crown 16 gauge air stapler that will shoot up to 2 inch staples. I would get a bunch of 1-1/2 inch staples, a big bottle of wood glue and go to town.

Might be a good excuse to buy a few more toys

 

[Glenn9643]

"Most used plywood gussets at the joints for the trusses. The thing that I didn't care for about using plywood gussets is that they require lots of nails to handle the forces and cutting out the gusset plates would take quite a bit of time. In addition to taking lots of time to drive, I get nervous putting too many nails in a small area. In the middle of the night I'd be listening for the wood to split under a heavy load!"

I agree with Bob on all points. Lots of nails doesn’t translate into lots of work when you have the proper tools. If you’re considering building a wooden framed building you should have a good pneumatic framing nailer. You can use SMALLER nails when nailing the trusses together and splitting won’t be a problem. The nail gun will make the job much easier and for me would pay for itself in one project like yours with faster work and less back/shoulder pain. The staple-gun that Bob mentioned would be much lighter to handle and faster to use but would be added expense that you might not want right now.

 

[skid mark]

Thanks for the input so far.

I should point out that I do have an air nailer so my concern isn't that I'd have to manually drive all of the nails.

Everything I read says that shear developers are an excellent method of joining 2xX lumber.

Depending on the thickness of the gusset plates, type and quality of the lumber, an 8D nail (recommended in the plans at the site mentioned above) will have a load capacity of around 80lbs. I have no idea what the load capacity of a 1 1/2 inch staple is.

A split ring connector in similar circumstances will have a load capcity of at least 2100lbs, equivalent to 26 8D nails. The capacity of spike grids exceeds that of ring connectors by 20% or so. If you are interested and dive into the barn plans on the ag site, you'll notice that the truss plans listed above really stand out. Those plans allow for a 40 foot span, a relatively low 4/12 slope and a four foot spacing for the trusses. All of the plans which specify gusset plates and nails have higher slopes and/or two foot spacing between trusses. A couple sets of plans have 40 ft spans and relatively low slopes but they use double top and bottom chords.

As was said above, I guess it boils down to one's perception of what would be the easier solution. Personally, I would find it much easier to drill a single hole through two 2xX's, insert a spike grid and then put a bolt through it than cut gusset plates out of sheets of plywood (which I hate to wrestle with) place one on each side of a joint, nail in 15 or so nails and then flip the truss over and do the same on the other side.


Mark

 

[SPIKER]

Mark:

yes it is a lot of work either way really. my barn was hand built trusses, gambrel, multi pitch, with free span across my 3nd floor, of 38'. they used plywood cut outs, WITH PL400 on each side, and staples, I later went back and added gap fillers, UNDER the truss plywood cover plates, which were cut form 2x6 in a large triangle shape. I too added PL400 and used 2.5" #8 nails driven in each side of the plywood AND into each joint of the truss plates which were made p form 2x6's too. mine uses a full 18' 2x6 going up at a steep angle, to a 2nd 18' 2x6 that forms 1/2 side, other side same, and in between is a 20' 2x6 which has a center 2x6 about 6' long tiring into the top center joint.

Kind of like THIS below but that top section is not flat but a 4/12 or so pitch the sides are very steep like as in can't simply WALK up the outside roof even with grippy shoes on the asphalt singles...

_ __ _
/___|___\
/ \

anyhow just wanted to point out that each side is not filled in at the FLAT to the Steap side plates with the added filler 2x6 only reason is that I intend to FINISH off the 2nd floor someday and needed NAILER for drywall or OSB depending on what I USE up there... office space. or uper living quarters.
Mark M

 

[v8dave]

I am currently having a shop built. The attached photo shows an installed arched truss with nail plates holding the joints. All the shiny spots are the nail plates--one at every joint. These are kind of like a cheese grater, only with 1/2 to 3/4 inch teeth. It is this plate/teeth that are nailed to hold the joint together. You may be able to use this type of joiner.

I know you said low cost was an objective. But, it may worth your while to investigate prefabricated trusses. I had these trusses made to order at a local truss company. When I placed the order, I thought the price was fair. But after seeing the price the general contractor paid for a load of wood, I believe the price was great! The truss company gets the wood at a good price and isn't reselling it at "yard" prices. I believe that in the end I only paid a slight premimum over the cost of the raw wood [bought in a lumber yard] for the prefabricated trusses. And, they delivered the trusses to the roof! Check out your local truss company, you'll need a truss plan for them to provide an estimate, you may be surprised at the reasonable cost. Then again, maybe not...

 

[rlee6]

Could someone kindly tell me how much it costs to build a barn? Some kind of ball park figure per square foot? I am looking into 25' x 40' (1000 square feet), concrete slab. Just the barn itself, no interior.

Another related question: Should I get the power before the barn? What I mean is if the building cost goes up if electricity is not available.

Thanks.

 

[Egon]

Me, I'd buy the trusses. The difference in cost of home built to purchased is not woth the effort. Easiest to check out costs. You'll be surprized at how fast the cost of the metal plate connectors add up. Also take into account final accuracy of the truss.

Power on site is always a nice thing when building. Otherwise its manual or a generator must be used for the power tools.

Egon

 

[mikim]

to parrot what others have said .... you need to price out your trusses made to order. then compare that to what your materials price would be. when I was helping a friend with a 40 x 40 garage - he calculated that we could build the trusses cheaper - and it would take us (2 of us) an average of 30 minutes per truss - factoring in time for building the jigs - at a cost savings of $10 per truss. OR for that extra 10 bucks he could use the phone and have them delivered in 2 days. they came all bundled up and ready to go.

 

[chucko]

Is there going to be an inspection on this barn? If so they may give you a hard time if you build your own trusses where they would not if you bought them. Have you thought about conv framing with a ridge beam/board and rafters if you don't want to buy trusses any lumber yard should be able to size your rafters for you.