OK, like they say: "size doesn't matter". As a poster mentioned, it is easy enough to remove (have a builder) the window and window frame. That will give you a whole pile more space. If that doesn't work, just cut a bigger hole in the side of your house. There should be nothing to stop you.

I built a 17' trailer sailer in my Garage. 17' was the biggest thing I could build there. I always knew it was going to be too big to fit out the door.

One Christmas (champagne breakfast) when the time was almost right and I had heaps of guests about I unbolted the tilt-a-door, took off all the fixtures and sawed off a stud about transom height and we bought my baby out into the real world.

I replaced the stud, secured it with gangnails and patched it up. That was about 7 years ago.

Nothing is a problem

Go for it - Pete