Raising the roof

[bma4235]

Hi Everyone ,
I am very new to this forum, and I would like to pick some brains about my proposed project.
I just moved house and had to say goodbye to my 3000Sq ft barn and workshop !!
My new property is right on a river and local regs prevent any structure from being built within 40 feet of the water,
So I have few options for a new shop.
The only reasonable one is to add a second floor to my 20 ft by 20 ft garage, and I would really like to do this without tearing off the roof.
The garage is built with cinder blocks, so I am proposing to do the following
My plan is to first reinforce the roof by adding additional ties and basically beefing it up wherever makes sense.
I will then remove every third cinder block from the top of the walls so I can insert bottle jacks.
I will then raise the roof just enough to add another course of blocks, and keep repeating this until I have raised the whole structure by about 8ft.
Does anyone see any major problems with this approach.
Any advice/suggestions are most welcome. I can provide construction drawings if needed.

 

[nadogail]

I recall reading the modifications made to the White House during the Truman administration where they jacked up the White House Dome and poured concrete around the jacks.