wall opening

So first of all - this isn't something I would attempt myself - but I would like some advice as to which path to take: The green is the proposed opening. Steel number one just holds up a flat roof, steel number two is there to prop up steel number 3, which is bearing the load of the side wall...

I’m creating an opening (Proposed 1700mm wide) in my rear external ex solid wall (it has been rebuilt using cavity with a width to match existing, 230mm, just in ground floor and half length of the wall). There is a small window and a 900mm door in that wall panel I want the opening in for the...

I am to open the wall between the kitchen and dining room. The wall is bearing the load of joist of a bedroom above it. There is no other wall above it nor stud wall just the joists. I am looking at installing 2700x100x65 lintel. My question is what is the minimum length on the breeze block...