And although almost any roof can be raised the cost of raising a very large or complex roof may outweigh the benefits.
Raising garage roof height.
Additional support may be needed if the roof is not very stable.
In the first post it says he wants to raise the ceiling height of the garage.
My issue is that my garage ceiling is too low at just over 6feet i keep hitting my head on the lights.
Consult a contractor for an estimate.
But it is a big roof and expensive to do that for a small return.
You could brace the inside of your garage and use hydraulic lifts to raise the roof.
You might also try raising the actual garage itself but this obviously has structural challenges.
I know that i could take off the roof add a brick layer and then put roof back on.
There is only two ways to do that.
Raise the whole building or raise the roof.
Raising the roof and leaving the walls in place is a little easier but the task of disconnecting the roof from the walls is more difficult than disconnecting the walls from the floor.