In this case, it may be possible to use a hot-rolled channel instead of the cold-formed z-purlins. Hot-rolled channels are widely available and have well-established load tables, which can simplify the design process. However, it is important to ensure that the hot-rolled channel is compatible...
As a builder, I advise leaving a gap of an inch or so between the window and the soffit. We recently installed windows in a private home. It's quite large, 480m2. And I'll tell you there were such moments as wooden beams sagging on large openings. And the good thing is that there were smart...