I’m about to start a project to line the inside of my shed with a frame so I can have either plywood or vj board walls.
While I’ve done quite a fair share of DIY jobs in the past, this will be quite a new and major project for me, but one that I’m ready to tackle.
My question is how I am best to secure the frame to the shed. I’ve assumed that I need to build my timber frame inside of the existing metal shed frame so that the timber is flush against the sheet metal wall, but now wondering if I would be better off building the timber frame on the outside of the metal frame (thus reducing the size of the room by the width of the timber frames)? Either way, I’m unsure of the best way to secure the timber frame. I’ve seen some examples where they are secured by screws from the outside of the shed?
here’s a couple of photos of the inside and current metal frame. Hopefully my question makes sense, but any advice would be greatly appreciated!

