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dgbldr
05-25-2008, 02:23 AM
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

Lavrans
05-25-2008, 02:56 AM
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.

marson
05-25-2008, 08:30 AM
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.

donstump1@yahoo.com
05-25-2008, 10:02 AM
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

Richard Birch
05-25-2008, 10:19 AM
This is usually easy and safe.

http://www.jlconline.com/cgi-bin/jlconline.storefront/483967ad06c1abe427170a32100a066b/UserTemplate/82?c=a878091c7e55daf4bc82267c47e62df0&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

David Meiland
05-25-2008, 10:28 AM
+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?

marson
05-25-2008, 12:03 PM
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.

parkwest
05-25-2008, 12:41 PM
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.

Lavrans
05-25-2008, 12:43 PM
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? :-)

parkwest
05-25-2008, 12:51 PM
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?

dgbldr
05-25-2008, 03:37 PM
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

David Meiland
05-25-2008, 11:29 PM
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.

Joe Carola
05-26-2008, 12:14 AM
Any other ideas?

dg

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

johnny watt
05-26-2008, 12:40 AM
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.

dgbldr
05-26-2008, 12:43 AM
OK Joe, I'll bite. Tell us how you're going to stick frame a roof with a bunch of unskilled volunteers.

dg

NW Architect
05-26-2008, 01:38 AM
I would be one of those unskilled framers, were I to be on site, so here's the tricks I'd use:
o Precut 22-1/2" blocks for along the wall plates. Preinstall A-35 clips on them. Tack them up a 2' intervals, hanging from a stud, where they will be ready where needed
o Precut several 22-1/2" top-of-chord braces and sister them to longer pieces (say 30")
o Precut 22-1/2" ridge blocks and pre-install a framing clip (A34 or A35) on one end
o If folks cannot toenail, invest in hurricane clips (and shorten the plate blocks by the thickness of a nailed up hurricane clip)
o No clue how best to muscle the first truss in place, but once it is in place:
o Fasten it to top plate with hurricane clips. Yank the block off the stud and butt it next to the truss and fasten it down with its A35.
o Maneuver the next truss into position and kick it up against the installed blocks. Two volunteers hold it there. Up top, from ladders, two others lay those 30" pieces Over the top chords and nail down into the top chord to both space and brace the top chord.
o Install hurricane clips. Install blocks at the wall plates.
o Install ridge block. Use clip on one truss. Nail through the other truss into the end of the block
o Repeat
o Follow the YouTube guideline for bracing . . . or some other protocol


Rolling scaffolds about 4' high for the folks working along the plates

Little Giant Ladder(s) for the folks working the ridges. Set up as a step ladder. If pitch is not too great, the ladder can top out at bottom of chord and volunteers can stand safely straddling the top of the ladder. Otherwise, close it and move with each new truss

My $0.02 . . . and maybe not even worth that

Joe Carola
05-26-2008, 08:20 AM
OK Joe, I'll bite. Tell us how you're going to stick frame a roof with a bunch of unskilled volunteers.

dg

1) You precut all the rafters

2) Medium-skill crew leaders and unskilled volunteers nail up all ceiling joists off bakers scaffolds or ladders

3) Lay down a row of sheets of plywood on top of ceiling joists at plateline and ridgeline

4) 28' span with a 6/12 you have roughly 7' to top of ridge, build a 2' scaffold
5/12 pitch 6' to top of ridge, no scaffold

5) Unskilled volunteers pass rafters and ridge up

6) Nail two rafters on top of plates front and back and slide ridge in between and brace

7) Finish nailing rafters


Your safe, you have a deck of plywood to walk on, no lift heavy trusses, no balancing trusses on the outside plates or scaffold, no cutting 22-1/2" blocks, no bracing, no walking on trusses...........etc.

How can anyone here expect unskilled workers to set 28' trusses and work safe?

The houses are all the same width and they are 24' and 28' with a 5/12 or 6/122 pitch. Pre-cutting every rafter is the same as having a truss made, just make sure your walls are 24' and 28'.

Tim Uhler
05-26-2008, 10:09 AM
Yes, tell them to stick frame the roofs so that someone doesn't get hurt/killed. since noone is experienced.

Joe,

I'm in complete agreement with you about the saftey. When the ceiling joists are in, you have an entire platform to frame off of. When the ridge is as low as it is in your example, things go quickly and very safely. And you can use less skilled labor.

I've done that quite a few times in the last few years. When I get new guys, it takes no time to show them how to nail rafters, string the ridge and block. Plus they have fun doing it.

Joe Carola
05-26-2008, 10:40 AM
Joe,

I'm in complete agreement with you about the saftey. When the ceiling joists are in, you have an entire platform to frame off of. When the ridge is as low as it is in your example, things go quickly and very safely. And you can use less skilled labor.

I've done that quite a few times in the last few years. When I get new guys, it takes no time to show them how to nail rafters, string the ridge and block. Plus they have fun doing it.

Tim,

I don't care what anyone says, setting trusses with unskilled labor is not safe at all compared to stick framing a roof with unskilled labor.

Maybe they have to use trusses and can't stick frame, I don't know, but if they have a choice and are concerned about safety(which they should be) sticking framing these one story 5/12 - 6/12 roofs is much safer, faster and easier to frame with unskilled labor.

dgbldr
05-26-2008, 11:58 AM
Thanks Joe and Tim. I see your point. They don't have to use trusses, just the way they've always done it. That can be changed. I can see putting down ply/OSB to work on and then taking it out and sheathing the roof with it.

I'm trying to envision getting up the end pairs of rafters and the ridge with unskilled labor but you are right, with the "floor" to work on you can have a bunch of people up there holding up rafters.

Could probably use a few of the Truslock tools to keep the joists from rolling while they are working up there. So they don't have to make and nail blocking.

dg

Don_P.
05-26-2008, 01:39 PM
I like Joe's idea.
I do see the entire idea as flawed. An inexperienced person falls off the safest situation you could make, which was still a dangerous situation, who is everyone in the room going to be pointing at?

I was in the habit of allowing homeowners to use my scaffold set ups to do sweat equity work. One mentioned that she almost backed off, temporarily forgetting where she was. That concept had never entered my mind and in the same instant sounded an awful lot like a convincing argument.

You are trying to make a safe situation which is commendable. I think I would pass the unsafe situation upstairs and ask how they wish to solve their problem.

Joe Carola
05-26-2008, 02:41 PM
I'm trying to envision getting up the end pairs of rafters and the ridge with unskilled labor but you are right, with the "floor" to work on you can have a bunch of people up there holding up rafters.

Don't set he gable ends first. Come in to the second or third rafter and set those first front and back. Lift the ridge up in between and the rafters and they will hold the ridge in place and set he ridge height. Brace and fill in.

Set the gable ends last with one of the medium-skilled crew leaders.




Could probably use a few of the Truslock tools to keep the joists from rolling while they are working up there. So they don't have to make and nail blocking.

dg

Using strongback solves that problem.

David Meiland
05-26-2008, 05:18 PM
I think you guys are making a big deal out of nothing. Not all inexperienced help are stupid, and a good person in charge with a good plan can make it happen safely with 26' low-pitch trusses. The biggest issue is carrying them flat and not breaking them.

Opinion only, worth price charged.

Joe Carola
05-26-2008, 05:31 PM
I think you guys are making a big deal out of nothing. Not all inexperienced help are stupid, .

David,

Since when does inexperience mean stupid?

It has nothing to do with being stupid. What's safer, placing unskilled labor lifting up trusses and trying to balance, block brace........etc them, or having unskilled labor walk on plywood and nail rafters to a ridge.

David Meiland
05-26-2008, 05:42 PM
Well, it might be more dangerous having inexperienced people make a bunch of rafter cuts with a skilsaw. I think the trusses can be done quite easily if they're 26' 5:12.

Joe Carola
05-26-2008, 05:44 PM
Well, it might be more dangerous having inexperienced people make a bunch of rafter cuts with a skilsaw. I think the trusses can be done quite easily if they're 26' 5:12.

David,

Read my post #17 to DG. I said that he cuts the rafters, not the unskilled labor.

David Meiland
05-26-2008, 05:54 PM
Is that how Habitat works, the skilled supervisor/volunteer does the scary stuff? If so, just get 3 of them and set the trusses!

Joe Carola
05-26-2008, 05:58 PM
Is that how Habitat works, the skilled supervisor/volunteer does the scary stuff? If so, just get 3 of them and set the trusses!

I don't know how they work, but obviously there must be a problem with unskilled labor setting trusses and safety, so something should be done to make it right.

Railman
05-26-2008, 10:26 PM
I'd do a 20-24' pick inside at the rear, & front wall at about 3 ft off floor, or whatever ht makes the wall at shoulder height. 7' rolling scaffold is way too tall, & wouldn't make it past all the wall braces. I would also run a temp 24 oc framed wall all the way down the middle, leaving a 6' or so gap in line with where the trusses would be carried through the front wall. If no door, make a hole! Cary trusses inverted with peak down. Now you can use two teams carrying trusses into to home, & setting them on the walls, & two teams sliding them across the walls, while only being 3' off floor, walking on picks. Shoulder ht is a very easy height to slide trusses at. Use better help to set trusses to line, & run ridge, & fasten. Again the hardest part is to set the gables, but if you take your time, it really shouldn't be that bad.
Joe

dgbldr
05-27-2008, 01:09 AM
I don't know how they work, but obviously there must be a problem with unskilled labor setting trusses and safety, so something should be done to make it right.

Yes, Joe got it. Actually, a person who got injured a while ago is a very experienced former framer. Not stupid in the least. It's the nature of the activity. For those of you who haven't experienced Habitat, it's nothing like a regular construction job.

There are a lot of unskilled and inexperienced volunteers all over the place. The few experienced people are running around supervising and directing total strangers. At any given moment there is someone who needs help or direction. Or might be doing something dangerous inadvertently. The experienced people can do only a small amount of the most skilled work and need to keep an eye on the others while doing it. It's intrinsically harder and more dangerous than running a crew.

After much observation and thought, I decided that the best way to get things done safely is to simplify and bring the tasks to a level that an average person off the street can handle under supervision.

dg

dgbldr
05-27-2008, 01:20 AM
Is that how Habitat works, the skilled supervisor/volunteer does the scary stuff? If so, just get 3 of them and set the trusses!

I'm not sure me and 2 other "experienced" guys I've never worked with (all 3 of us NOT framers) would make for the safest truss setting crew either, but yes there are tasks that are done by the supervisors. Just trying to eliminate the scary part :)

dg

parkwest
05-27-2008, 09:37 AM
From what you describe as a typical HFH work environment, it sounds like the whole company should be shut down due to safety isssues on the jobsite.

Anyone see accident reports on these guys?

Joe Carola
05-27-2008, 10:13 AM
Dg,

Your framing all interior walls also before you set trusses, right?

Railman
05-27-2008, 10:36 AM
Dg,

Your framing all interior walls also before you set trusses, right?

If it were me, I wouldn't, unless you want to drag trusses over the walls from the outside, or have a crane available. It also limits how many people you can have working on site at the same time. If interior walls are done after roof, you could have some working on interior, while others are doing shingle, & exterior trim etc. What do you do with extra help while your framing interior walls? It's also less cluttered, & easier to maneuver around the interior without all the added walls. They key here is the level of help that you have to work with, along with the number of people involved.
Just my .02
Joe

Joe Carola
05-27-2008, 11:56 AM
If it were me, I wouldn't, unless you want to drag trusses over the walls from the outside, or have a crane available. It also limits how many people you can have working on site at the same time. If interior walls are done after roof, you could have some working on interior, while others are doing shingle, & exterior trim etc. What do you do with extra help while your framing interior walls? It's also less cluttered, & easier to maneuver around the interior without all the added walls. They key here is the level of help that you have to work with, along with the number of people involved.
Just my .02
Joe

Joe,

I frame every single wall in the house and additions, never go back later.I keep everyone busy. It's a system that works and has always worked.

Joe,

If your talking about Habitat, maybe that will work. I thought you were talking about framing in a normal situation.

Railman
05-27-2008, 12:15 PM
Joe,
I framed for about 20 years for my oldest brother that ran at times over 20 crews. I've pretty much done, & seen it all. I understand perfectly, & agree with you about what your saying about normal operating procedure for everyday production, but that's not what this thread is about.
Joe

Joe Carola
05-27-2008, 01:40 PM
agree with you about what your saying about normal operating procedure for everyday production, but that's not what this thread is about.
Joe

Joe,

This thread is about Habitat, but if you and I were to work on a project we would have to consider bringing normal conditions into the project depending on how many people are there and who knows what. If they have 10 people working on a house, I doubt framing the interior walls would be a problem. If they had 30 people working on one house maybe the interior walls would be a problem. Who knows what goes on there. We both wont know until we've tried one.

dgbldr
05-27-2008, 02:06 PM
Yes normally they erect all interior walls before they set trusses. Not a problem manpower-wise. But remember that in a Habitat build you rarely know how many people are going to show up on any given day and/or their skill level. So matching jobs to manpower can only be done on a crude level regardless of the tasks involved.

Typically they pre-build all walls in 10-12' sections at the shop, warehouse them and trailer them to the site, which is always within 1 (one) mile or so of the build site. Occasionally they stick-build the walls on site.

One reason they do trusses is that they can add some "features" at little to no cost. This is important as the houses are very simple and many are on adjacent lots, so they try to make them look a bit different, either inside or out. One such thing is to put a V in the bottom of some trusses to make a "vaulted" living room ceiling, for example.

The other reason for trusses is that they are arguably more "green" and they want to be green. The reasoning is that you can build trusses with smaller and shorter pieces of lumber, which wastes less trees. Also, the total mass of wood used is claimed to be less. I haven't done a thorough analysis to verify those claims.

dg