How to fit a pvc window to a corrugated metal shed

Question

I have a corrugated metal shed which i want to fit a pvc window. I am not so sure how should i approach to this. The shed looks like the one pictured below but there are 2 vertical perimeter channels on the gable end ( Same as the side walls in the picture)

I know these bars wont carry the load of the window alone so i need to build some sort of a supporting timber frame but i need some advice on this since the gable end of the shed usually takes some strong winds and a lot of rain.

Also, whats the best way to water proof groove shape of the metal sheeting? expanding foam?

groove depth is 32 mm on the sheets and the supporting horizontal perimeter channel behind is 35 mm Upvc window is 70mm thick with 60mm slot at the bottom

Here is crappy thing i drew on ms paint which might be useful :) grooves are actually running vertical, so not like the drawing

Answer 1

Actually they probably will carry the load just fine. The general process is this

1. Buy the window size you want in vinyl. It should fit between the framing members (you do not want to cut those)
2. Buy some aluminum channel bars ("C" shaped). You'll need 4 at least as long/wide as your window. Construct a frame from these pieces, using two channels on the sides to support the top and bottom. You'll have to cut the top and bottom to slide over the shed wall itself. The finished frame should wrap the opening, leaving just enough room for your window. If the channel isn't painted, now is a good time to paint it. Caulk the top and sides with the best outdoor caulk you can get.
3. Insert the window with some exterior caulk to glue it in. Screw through the window flanges into the frame from the inside (short self-tapping screws should work)
4. Get some wood or metal (wood is probably cheaper) and run it vertically between the horizontal supports of the shed frame. You'll want to L-bracket it to the frame or floor and screw through the outer shell to this vertical support. This will help support the weight of the window and keep the sheet metal wall from pulling away from the frame
5. Make a flashing (spare sheet metal will do) to go over the top of the window frame. It should extend at least half an inch beyond the window. This will help keep some of the rain out of the top channel (caulk should prevent the rain from penetrating but you don't want water freely pooling up there either)