...So I kept my eye out on Gumtree.com.au for some free awning windows to encase the area. I got one from Sim n Tari from a renovation project they did, and another four from a dude on Gumtree. I still have to do some more sanding and staining, including some flashing work to cover up some joinery that's exposed, but overall it's getting there. I found an old trolley wheel on hard-rubbish and turned it into a jockey wheel for one of the windows which is mounted on some large gate hinges. Worked out pretty well. Will get around to latches soon enough.
I have a nice lil' workshop in there now!! Stuff will stay dry, and I can still get large tables/projects in and out through the massive gate doorway. The entire thing can be lifted off the hinges and removed if required. Very pleased. Xave is already trying out the work space!! :D
**Update**
I need to get some flashing over the joinery.I scrounged some thin plastic sheeting from work. We get all kinds of materials from suppliers as protective layers between a pallet and it's stock. Usually cardboard or corflute, but sometimes expensive melamine, nice ply, or MDF. I got lucky with this plastic sheeting, it'll work great as flashing.
It chips out badly on the table saw. Had to cut this with scissors. Hands pretty worn out after 4x2.4m strips.
Came up looking pretty good.