Hi All,
I am currently framing a garage in AZ, we are using trusses with 3-12 pitch, Gable roof, 20′ span and 30′ run, 24″ O/C, 2×6 walls (simple rectangle). All of my framing experience is with stick framing back east so I am looking for a quick run-down on truss installation.
My plan was to set both gable ends plumb and secure them diagonally to steaks at ground level. then run a line from peak to peak and align a common to the line and toe nail and then on to the next common. Run a 2×6 parallel to the inside of the gable’s lower cord to tie the lower cord to the top plate..? Each truss get 1 – H2.5. Sheathing is with 7/16 OSB & 8D ring shanks and clips.
Also planned on adding 2×4’s across top cords for lateral support until sheathing is on and adding in 2×4’s on the top edge of the lower cords along the run.
Any feedback would be appreciated.
Thanks,
Chris
Edited 4/25/2006 3:06 pm ET by ChrisV
Replies
I would set one gable where it goes, and brace as said. I run a string on the outside of the building at the end of the tails+1 1/2 inch. (assuming a small overhang) I run the rest of the trusses to that string with a 2x4 to check my spacing. Then I set my end gable.
How are you flipping these trusses?
I hope Chuck Norris never potato sacks me!!!!
bstcrpntr --- I hope to grow into this name.
My plan was to set both gable ends plumb and secure them diagonally to steaks at ground level.
What sort of steaks - T-bone? Porterhouse? Frankly, I think them steaks at ground level gonna' get et by the dog . . .
Forrest
Maybe BossHog will reply, but I think you'll need some internal permanent bracing. When we set trusses, the truss maker always sent us a sheet that specified where the braces had to go.
These are only 20' trusses, and low sloped ones at that. There won't be any braces required in something that small.
Every so often, I like to stick my head out the window, look up, and smile for a satellite picture.
I would set them as bstcrpntr would, but skip them string on the tails. Just make sure your walls are straight, and use the top plate as a guide for keeping the truss heels all lined up.
Mike
Arcticcat does it the way I do - String the walls and set from one side.
Seems to me that running a string at the peak would be a pain in the neck - It would always be in the way.
If you make a mark a little more than 8' up from the overhang and run your braces above that, then you can stand on the 2nd row of plywood and pull the braces off from there.
For hand flipped trusses, we start on the gable end and often apply the sheathing and add any backers for the trim on the truss before lifting. We make "strongbacks" which are a couple of 2x6 nailed together in a T. These get spiked on the gable wall so that they stick up above the top plate a couple of feet and prevent the truss from falling off the end. I like to have a few bundles of 1x3x16' strapping for temporary braces. A person can go up a step ladder and nail a piece of 1x3 to the top of the gable truss. The other end gets tacked to the top plate out as far as it will reach. This basically puts two, one on each side, angled braces that reach from the top of the gable truss back down to the top plate. You can also tack to the strongbacks if needed. Brace the gable truss plumb, now.
We take care when stringing and bracing the walls straight. We also get very nice trusses, so, just making a mark on the bottom chord to line up with the top plate keeps things straight. You have to be careful when trying to set trusses to a strung line. If one touches, it will throw the line off.
With the gable truss braced with 1x3, you can flip up three or four trusses under the 1x3 without having to move it. The braces help to steady the trusses as you flip them up. We also start running a horizontal 1x3 up at the peak that is laid out for your centers. This way you don't have to be grabbing a tape or using a spacer block. Line up the truss with the mark and tack it, also tack into the diagonal braces. Eventually, you will have to let the end of the angle brace, that is tacked to the top plate, loose. About this time, you start a second diagonal brace that runs from the gable truss bottom to the top of the last placed truss. Now you have four or five trusses standing with an X of 1x3 on each side of the roof, tacked into each truss. This will be nice and strong and keep everything square and plumb, if you did the layout correctly. Temporary cross bracing, both sides, on a small roof like yours is a bit more than needed unless you leave it overnight.
The horizontal 1x3 is probably sticking out past the last placed truss several feet. You can lift several more trusses just using that to keep the tops steady. As soon as a few more are standing, continue the X bracing. You need a certain amount of space to swing the trusses up. You have to flip up two or three and just lean them, temporarily, against the last braced truss. Lift the other gable and slide the leaning trusses to their places. You should pull out the long tape and check that the measure from peak to peak is the same as the outside wall. It's also a good time to sight down the rafter tails, just in case.
Your roof shouldn't cause any problems, but, it's never a good idea to go away without good bracing. It's also not a good idea to just get one side of a roof sheathed and leave. Here in New England, we use strapping on our ceilings that runs perpendicular to the bottom chords at 16" OC. You need a nailer on the gable walls for the strapping. We normally spike a 2x6 down flat ways so that it sticks out beyond the top plate. It's easier to install before sheathing the roof. The 1x3 temporary bracing gets recycled for the ceiling strapping. The horizontal running pieces already are laid out for the centers, you just have to cut some off the first piece. We wait until the sheathing is on before installing the permanent truss bracing. We also place the center run of strapping or, temporarily space the bottom chords on the centers, before the permanent bracing.
Beat it to fit / Paint it to match
All,
Thanks for the info, I will let you know how it went.
Chris
I do it pretty much the same as you do. The one variation might be that with smaller trusses I will set and brace the first gable, bring in the first common truss, then attach a 1x brace from the gable to the first common inside the trusses rather than on top. Bracing inside requires sliding trusses into place rather than rotating them up, but then there's no temp bracing to remove or work around later. Using 1x4 x 8' works well. This is easy with stuff around 20' or so.
For big stuff that I can't move by hand with another guy I brace on top.
I always pull a string along the ridge once they're in place. I can cut the tails if I have to but not the ridge, and it's easy to bang trusses over a bit to be on the line. Tails are not usually accurate enough to avoid cutting them.