I removed some siding and and re did the trim on the top of the door and then recovered every thing with aluminum and installed new rubber garage door sill around the opening.
How to add height to garage door opening.
For a garage attached or detached from your house of around 18 x 24 feet most popular width for a garage door is 16 feet.
This lumber will be used to attach your garage door track and a portion of your assembly.
Cut two 2 x 6 pieces of lumber and attach to the face of the wall running from the edge of your garage door jambs to the ceiling of your garage.
One way to do it would be to get wall extensions for the entire the garage and then cut the roof of the garage off lifting it up to the height you want it.
For a shed the best size for installing a garage door is 8 x 14 feet.
Pull a measurement from the floor of your space to the ceiling next to the door opening.
Standard single car garage door widths start at 8 feet for single car garages and move up in 12 inch increments to 10 feet wide.
Double car garage doors typically start at 12 feet wide and move.
Because garage doors are usually sized to snugly fit the dimensions of the garage itself making the door larger usually means making the garage larger.
If you have an rv the door can go up to 10 feet.
2 a double door.
Then the garage door would be 6 x 6 6.