Beam jacking idea....

....or accident waiting to happen? :-)

Just wondering if anyone has seen some version of the diagram below.  I may need to jack a roof beam beyond the distance the jack's normal reach.  Was thinking that the load binding idea could be used to "hold" the support beam at the new height while a new shim block was added to the screw jack to continue with the upward raising of the support and the roof beam.  The ideas is that metal bands would hold the outside boards in place even though the central laminated beam could still slide past them in an upward trajectory.  Once the final height was reached, the open space where the jack is would be filled with extra support planks so the the outside boards were not the sole bearers of the weight.

Thoughts?...Thanks.

(Also, where the chain/cable comes in contact with the board ends would be steel guides to that the chain/cable would not just bust up the board ends from the force applied.)

Get yourself a floor jack, the kind they use to prop up the floor from the basement.  They have a lead screw for adjusting their height

They cost about $50-$60 and look like this:

Hi John, I haven't seen this approach before. I have some experience as a project manager that had houses raised for foundation repair or crawl space clearance though. If the beam sits in a pocket just jack it up and shim at the pocket, lower the Jack, shim under Jack etc. the trickiest part is stabilizing the jack and whatever it is sitting on.

Some more info is required to give a better opinion.

Is this a ridge beam?
Are there rafters attached to the beam?
Is there sufficient support for the jack's point load?
Is it a vaulted ceiling?

I have used dunnage to support beams. Jack up, support beam with dunnage, lower the Jack, Raise jack higher up...etc till beam is at the desired height.

Dunnage can be almost anything like stacked pallets for instance. If jacking off a lower floor, dunnage sitting on floor will help distribute the beam load of and the jack, though I would keep the beam stacks and Jack stacks independent and perpendicular to the floor joists unless your jacking up off concrete. If using pallets, stack alternately on your way up. Most of the work I did was for clients and safety always came first.

It could very well be that I am over cautious and the system you posted may work very well. I just don't have past experience with it.

Peter that will work better than my long winded post...lol. I would emphasize that the Jack supports need to run perpendicular to the lower floor joists.

Thanks Peter!

Thanks for responses here.  There are actually two projects at hand and the idea posted by Peter VdW is likely what I will be doing for a basement support beam install to correct the "pitching" of a wall on the house that is making doors and windows bind and not seat properly.  For that project, the diagram he showed looks quite adequate.

I'm still also needing to tackle the problem in the past thread:  https://permies.com/t/49023/ft-quonset-roof-sagging-middle

The 40 X 80 ft quonset is still sagging in the middle of the roof.....only as you can imagine, it's now sagging a bit more since those photos. :-/  The photo in that thread on the March 20th entry shows the ridge-beam with the perpendicular side-rafters (that curve downward from the central ridge-beam).  The ridge beam appears to be no more than 2 X 6 lumber laminated to form the beam: My plan now would be to screw 1 or 2 boards (one on top of the other) into that beam so that the new boards lay flat against the beam and run ~12 ft of length at the "sagging-most" part of the problem.  These boards would be 2 X 8 inch, so would cover the beam (and a bit more) and would serve as the 'receiver plate' for the support beam that would run from the floor to the overhead roof-ridge beam.....probably best to use lag-bolts to secure these into place.   I'm waffling on using a 6 X 6 inch support beam or an 8 X 8 support beam for the jacking activity to push the roof upward.  Depending on how all of this goes, we would either leave the 'jackable' assembly in place and keep torquing upward from time to time or, if the roof raises rather easily, raise a telephone pole to serve as the main support beam and then lower the pressure down onto that pole when it is in place.  From there, we could remove the jacking assembly if desired.

I am still cognizant of the excellent advice in the linked thread above:  Jacking the roof without pulling in the sides could be disastrous if the roof ridge begins separating or if severe pressure builds up along the foundation down from where the upward-pressure is being applied.  The intention now is more of a "stop-the-bleeding" approach:  Get the ridge supported and then over perhaps several years, keep tweaking upward on the jacking system to slooooooowly push up the ridgeline to an acceptable height.  Worth noting again is that, due to flood plain map re-draws, all buildings on this property will likely be moved or demolished, so we are just looking to "stablize the patient" during our perhaps last few decades here.

So any additional suggestions are welcomed.  It's interesting to add that there seem to be some newer, more fine-tuned load binders out there that may work well as jacking assistants......just wondering if anyone has used them for such a purpose.  Thanks all!