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  • Setting trusses

    My local Habitat chapter had some close calls setting trusses with volunteers, so I'm looking to help them devise the safest methods for doing it.

    The houses are typically one story on crawl with roughly 24-28' trusses, 5 or 6/12 pitch. The walls are all built and sheathed when the trusses are delivered. The trusses are piled on the ground. There are no cranes or hoisting devices of any kind.

    How would you raise and set the trusses with a bunch of low skill volunteers and a couple of medium-skill crew leaders?

    dg

  • #2
    Re: Setting trusses

    dg- would it be possible to have the trusses set on the plates with a crane? A couple of the companies around here can send a boom truck out that can handle most single story jobs. That would be my first step. Just getting them up there from a pile on the ground is another step where you have amateurs walking plates- something I don't like to do anyway.

    Another idea is scaffolding. If you can have a run along the center (and sides too?) then the trusses can get walked up and are pretty quick & easy to set & plumb. 3 rolling platforms set at 7' plus would be great, with one for the center, one for each side.
    http://www.lavrans.com

    "He uses statistics as a drunken man uses lamp posts; for support rather than illumination." -Andrew Lang

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    • #3
      Re: Setting trusses

      IMO the worst part is getting them up on the plates without a crane. You could carry the trusses one at a time to a end wall, then lean it up peak down. Then fasten a rope on either heel and two people can pull it up. Slide it where it needs to go peak down. As for standing them up, when I've been in these situations, I've used a 2x4 push pole to push the top up to a guy riding the peaks. But it would probably be safer to use a rope, and have the peak guy on a stepladder instead of scrambling around in the framing, assuming 8' walls and a low pitched roof he should be able get to where he needs to be off an 8' stepladder.

      For me, the hairiest part is always getting the gable truss braced well enough so that the guy riding the ridge is safe. We usually run two 2x strongbacks vertically on the end wall, held with ledgerlok lags.

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      • #4
        Re: Setting trusses

        Is there a reason the truss company isn't setting the trusses when they deliver them? I can't remember the last time I saw a truss on the ground. All the truss companies in this part of California have trucks with booms on them. Maybe I'm missing something here.

        Don

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        • #5
          Re: Setting trusses

          This is usually easy and safe.

          http://www.jlconline.com/cgi-bin/jlc...7c47e62df0&p=1

          A couple of things to mention that are not in that article are;

          I run a temporary center support through the room if need. Most clear span up to 28’ can be done with one temporary support rail. (It is safer with two, or three, at 28’ and greater spans though, always make that call on the side of safety. The trusses are stocked on these and the men walk on them.) I always cut the rail (2 x 6 or larger, on edge) to fit in-between the walls exactly (to help brace and space the gable walls) and it needs to be just below the ceiling height as to hold the trusses from sagging to much in the center when they are initially spread/stocked on the building. This temp brace rail needs to be propped and braced fairly well too. The man standing the truss will use it to return back (walk on) to stand the next truss.

          Also, I nail the truss down to the plate, on layout, one nail at each end, before we roll it. (Like is typically done to stand pre sheathed walls on wood floor frames) Pushing the truss onto the marks is easier when it is lying down and having it secured at the base stabilizes it for standing. This is especially true for the first two trusses that have been blocked apart to form the starter box. (Nail the lower truss on layout before blocking) Don’t skimp on the number of blocks used to make the starter box. The more blocks, the more stable the box is. (roughly 4’ spacing is usually good)

          Btw, loading a truss roof with a crane with three or four trusses at a time is always easier than lifting them. If I have to manually lift them then I’ll often add a walk way to the temp rail system.

          There are literally too many truss setting scenarios imaginable to cover the best practice with one technique. Just be safe. Hopefully this will help.

          Richard
          One Length Method© by Richard Birch

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          • #6
            Re: Setting trusses

            +1 on getting a boom truck, whatever that takes.

            If I couldn't do that, I'd want 4 bodies to hand carry the truss and slide it up on the plates, and 2 more on rolling scaffolds inside the house to receive it and get it upright. It's hard to coordinate the movements of that many people if they don't know what they're doing. Can you shout loud enough to make it safe?
            Bailer Hill Construction, Inc. - Friday Harbor, WA
            Website - Facebook

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            • #7
              Re: Setting trusses

              Originally posted by donstump1@yahoo.com View Post
              Is there a reason the truss company isn't setting the trusses when they deliver them? I can't remember the last time I saw a truss on the ground. All the truss companies in this part of California have trucks with booms on them. Maybe I'm missing something here.

              Don
              Must vary depending on where you live. I've never ever heard of that. All the truss makers round here deliver them on a roller bed trailer. Which sucks cause you usually wind up with them in the middle of the driveway.

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              • #8
                Re: Setting trusses

                Maybe go to the OSHA website and see if they have any suggestions on how to "raise and set the trusses with a bunch of low skill volunteers and a couple of medium-skill crew leaders"

                And then at your weekly safety meetings you could go over these procedures with your low skilled workers.

                Maybe even get an OSHA inspector to come out to your site to check fall protection equipment and procedures.
                It is a simple matter of being patient. I do patience very well, except for the waiting part. That's the one aspect of patience that still bites me.

                I'm not saying I'm Superman. What I'm saying is no one has ever seen me and Superman in the same room together.

                ParkWest Homes LLC
                Working Man Online Store
                Living Healthy

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                • #9
                  Re: Setting trusses

                  Originally posted by parkwest View Post
                  Maybe go to the OSHA website and see if they have any suggestions on how to "raise and set the trusses with a bunch of low skill volunteers and a couple of medium-skill crew leaders"

                  And then at your weekly safety meetings you could go over these procedures with your low skilled workers.

                  Maybe even get an OSHA inspector to come out to your site to check fall protection equipment and procedures.
                  Hmmm.... Get a visit recently? :-)
                  http://www.lavrans.com

                  "He uses statistics as a drunken man uses lamp posts; for support rather than illumination." -Andrew Lang

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                  • #10
                    Re: Setting trusses

                    No.

                    Actually I believe I was requiring my guys to wear protective equipment and using "safety first" procedures before there was an OSHA.

                    I don't understand why contractors would help the competition. If we all could get exemptions from following all the rules and regulations, I bet we could grow to be one of the largest builders in this country, too.

                    Is it in the code that "all work to be performed by skilled workers" or is it just in all contracts?
                    It is a simple matter of being patient. I do patience very well, except for the waiting part. That's the one aspect of patience that still bites me.

                    I'm not saying I'm Superman. What I'm saying is no one has ever seen me and Superman in the same room together.

                    ParkWest Homes LLC
                    Working Man Online Store
                    Living Healthy

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                    • #11
                      Re: Setting trusses

                      Cranes and booms are not going to happen. Aside from cost, the truss work is done when they have enough volunteers. If there aren't enough, it's done at the next building date, often on weekends. If they rent equipment and they don't have enough people show up, they just wasted the rental fee. They need to work with tools and equipment they own and can get from their warehouse. They own a pickup truck and enclosed tool trailer.

                      I like the idea of rolling scaffolds. HFH could probably get some (buy or have donated) and they may be useful for other work as well. Also like Richard's idea of boxing together the first 2-3 trusses. I'm thinking of maybe even cutting ahead of time a bunch of 22.5" long pieces of lumber and blocking each new truss to the previous one as they go along.

                      My main focus is to have noone walk any plates or climb up on the trusses. Also can't build elaborate temp structures, because most volunteers can't use a nail gun or power saw. Think lots of people with hammers and nails. Only a couple on site who can use power tools effectively.

                      Any other ideas? Maybe I need to take a trip to Amish country :)

                      dg

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                      • #12
                        Re: Setting trusses

                        Originally posted by dgbldr View Post
                        I like the idea of rolling scaffolds.
                        If you set up a pair of 6-4" frames on casters you have a great working height for truss setting. Two setups like that, one along each wall, and two guys can get the trusses standing up (assuming they are shoved up on top of the plates laying down). Then they can nail them off to the plates. If you have more frames and casters you can set up a tower (~13' high) near the middle of the building and a third guy can be up there nailing a utility 1x4 to the top of each truss as it goes up. I love scaffolding, it makes things safe and easy and I find it very quick to set up. It is a bitch to store when not in use, though.
                        Bailer Hill Construction, Inc. - Friday Harbor, WA
                        Website - Facebook

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                        • #13
                          Re: Setting trusses

                          Originally posted by dgbldr View Post

                          Any other ideas?

                          dg
                          Yes, tell them to stick frame the roofs so that someone doesn't get hurt/killed. since noone is experienced.
                          Joe Carola

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                          • #14
                            Re: Setting trusses

                            Have them watch this.
                            http://www.youtube.com/watch?v=IALpipSsRQk
                            Then I strongly recommend getting some of these.
                            http://www.truslock.com/
                            They work great. I bet they would be even more of a godsend for amateurs.
                            Because amateurs can’t nail and they don’t know how to drive the nail just far enough before they put the truss on the line on the brace. So the truss will bounce off the line.
                            On the same note, I have always thought using hurricane clips would be good for armatures to set trusses with. Because, well, hell half the guys on a framing crew can’t toenail so save their life, and they always use the wrong size nails and they won’t hardly be able to nail through the metal gussets straight much less toe nailed. I don’t agree with your comment about the nail guns. Amateurs can use them good enough in a few minutes of practice.

                            I wouldn’t want anymore then 6 or 7 people around
                            String the walls then brace them.
                            Put layout on the top plates
                            Put up the braces to hold the gable.
                            Put layout on some 2x4’s for bracing
                            Carry the truss in with two or three guys at the most they are light.
                            Keep the truss peak down and lift one end up the ladder or hand it up to someone on the ladder.
                            Cheat the truss overhang out enough then do the other end.
                            Tilt the truss up as high as you can reach.
                            Get everyone out of the way on the ground and then use a 2x with a notch to tilt it up the rest of the way.
                            For the size truss you describe one brace on each side of the truss should do. top and bottom chord.
                            The brace should be as high as a man can reach to nail when standing on the bottom chord. These braces can hang over so that it will braces six more trusses …the next truss will easily tilt up underneath it even if it sags.
                            The last six or eight trusses will have to be placed on the walls and tilted up and stored on the opposite end because you will run out of room to tilt them up.

                            I don’t see why you can’t work off ladders for the two ends.
                            Even thought with raised heels it’s easier then ever to walk the plates.
                            I don’t see staging gaining you that much. Standing on a board spanning across the bottom chords is reasonably safe.

                            Probably the safest strategy would be to drive through a new track being built and talk three guys from a framing crew into coming over for two hours and setting them for you. In exchange your do-gooder weekend warriors could offer to detail their trucks or something.

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                            • #15
                              Re: Setting trusses

                              OK Joe, I'll bite. Tell us how you're going to stick frame a roof with a bunch of unskilled volunteers.

                              dg

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