Replies

1. 
   jimatgreatwhite | Feb 24, 2014 12:25am | #1

   I've done similar

   When I was framing houses with a small crew we used to rack  and sheath sections of trusses on the  ground. Nothing as big as what you have though.

   The racks were pretty stable.

   On a Habitat job one of the crews lifted their entire trussed roof, sheathed and shingled. ( Big Crane)

   I would think you are looking at a pretty large crane unless you can break it into a couple of sections, Are you re roofing?

   What about raising the entire building, less demo?, This would raise your headers at the same time. Brace to hold parrelell , some well placed jacks and up you go. I would Think a  House Moving company might work with you on this.

   If you went roof only as one peice , I would say some type of Purlin about 1/2 to 2/3rds up from plate to ridge. Nailed /lagged, maybe ledger or timber locks evry other rafter. Big crane (crane company should  be able to tell  you what size crane, and if they are comfortable with the job)with a spreader bar. Four penetrations in roof sheathing maybe eight feet in from each end. Straps around purlins and rafters.

   The sheathing IF NAILED PROPERLY  creates a pretty stiff system. I have never lifted any thing this size or with shingles installed. Checking that all rafter, ridge, collar tie connections are ROCK SOLID would be a good idea.

   Without seeing this I can not say it would work or not, just throwing a few ideas your way.

   Are you close to Denver?

   Good Luck

2. 
   jimatgreatwhite | Feb 24, 2014 12:26am | #2

   I've done similar

   When I was framing houses with a small crew we used to rack  and sheath sections of trusses on the  ground. Nothing as big as what you have though.

   The racks were pretty stable.

   On a Habitat job one of the crews lifted their entire trussed roof, sheathed and shingled. ( Big Crane)

   I would think you are looking at a pretty large crane unless you can break it into a couple of sections, Are you re roofing?

   What about raising the entire building, less demo?, This would raise your headers at the same time. Brace to hold parrelell , some well placed jacks and up you go. I would Think a  House Moving company might work with you on this.

   If you went roof only as one peice , I would say some type of Purlin about 1/2 to 2/3rds up from plate to ridge. Nailed /lagged, maybe ledger or timber locks evry other rafter. Big crane (crane company should  be able to tell  you what size crane, and if they are comfortable with the job)with a spreader bar. Four penetrations in roof sheathing maybe eight feet in from each end. Straps around purlins and rafters.

   The sheathing IF NAILED PROPERLY  creates a pretty stiff system. I have never lifted any thing this size or with shingles installed. Checking that all rafter, ridge, collar tie connections are ROCK SOLID would be a good idea.

   Without seeing this I can not say it would work or not, just throwing a few ideas your way.

   Are you close to Denver?

   Good Luck

3. 
   cussnu2 | Feb 24, 2014 08:05am | #3

   I would thinh rasing the whole thing would be cheaper too plus safer.  Run "headers" along the outside walls with the paralell wals obviously level with one another but the perpendicular walls different by the depth of your lifting beams.  lift the whole thing, put in prebuilt wall sections and lower it back down.  Remember though that regardless of where you insert the wall sections, you are creating a hing point and you have to do something to counteract that by tying the new wal section to old with more than just nails or bolts through the plates.  Your BI had better sign off on your plan but I woulld think plywood spanning the addition ON BOTH SIDES would be enough to counteract the hinge effect.

4. 
   dsremodel | Feb 24, 2014 08:28am | #4

   thanks for your thoughts. the shingles arein fine shape so i was thinking of saving them, although i 'm guessing thats an additional couple thousand pounds. the hinge point is a good one, the inside is unfinished so sheating that would be no problem, the outside is vinyl that i was hoping to leave pretty much intact so sheating that over the hinge point would be more of a pain.. the job is in illinois.i am goint to talk to a crane guy this week. thanks again

1. 
   cussnu2 | Feb 24, 2014 11:46am | #6

   BTW, no matter how new the siding is, you are going to face a clearly noticeable stripe of new vinyl in that band.  If you lift the whole building, you could use an alternative treatment on the bottom which would look much better such as a brick band or faux stone.  Not sure what you would do at the top of a wall to hide a new section unless you put up a band board at that point and switch to shingles from that point up.  That would look fine on the gable ends not sure how it would look with just a  two foot band on the other sides.

5. 
   cussnu2 | Feb 24, 2014 11:41am | #5

   Lifting the roof will involve a crane for likely two days you will also have to demo the garage doors and openers and deal with completely rebuilding that wall if the owner wants taller garage doors as well.  If you lift the whole building the garage doors and openers can stay in place provided you secure them and they will get naturally taller when you ift the whole building requiring just another section to be added on.

   My decision on approach would way heavily on what the owner wants to do with the garage doors.  If he wants them taller then I think the no brainer is raising the whole thing because lifting the roof is going to mean a complete reframe of the garage door wall to accomodate the taller doors.  However if the owner wants the same size garage doors then you are probable better off for the same the reason except that lowering a header in a whole building lift would be easier than raising a header in a roof only lift.  Lifting the whole building would also mean lowering any windows. 

6. 
   BossHog | Feb 24, 2014 05:56pm | #7

   Adding 2' to the walls as you described would create a "hinge" at that point in the wall. You'd need to put in full length studs to make the walls stable.

7. 
   sapwood | Feb 25, 2014 11:34am | #8

   I don't know how you're going to keep this stick framed roof intact during the lift and temporary placement on the ground. You shouldn't simply rely on the coller ties, they weren't designed for that task. Even with the addition of temporary ties at plate level, there is substantial risk of damaging the roof. Sure, it won't be unfixable, but you may loose the shingles.

   On the other hand, raising the existing building and adding a 2' lower section is safer for the workers and safer for the structure. Your customer gets the additional bonus of having an extra tall garage door for his extra tall garage. What could be better?

   The "hinge" issue is overblown. The new section is only 2' high. Talk to a structural engineer or knowledgeable architect. And having door and window headers an extra 2'  higher makes no difference whatsoever to the structural integrity.

8. 
   dsremodel | Feb 25, 2014 12:06pm | #9

   thanks for all your commentsi'm thinking raising the whole garage would be the way to go