Turn triple window into one bow window, structural concern

constructionframingstructuralwindows

I have a very old window probably from the beginning of this house in 1970's. Now I want to replace this old aluminum window with a bow window. my question is there are two posts of the triple window. Are they structural elements? Are they part of this triple window or the builder added them there to fit the aluminum double hungs?

The whole opening is as big as 120" X 56 3/4" I wonder the reason they put it there when they built this house. The window frame gave some support?

Thanks in advance.enter image description here

Best Answer

I can't think of any window that offer support. The frames are typically too weak and cannot handle the weight. The common framing for a door or window has a king stud (full height), then a crippler stud (shortened to support the header), a header (similar to a beam) over the opening, and at the bottom of the opening is a single 2xx4 or 2x6 depending on the framing, and the supporting studs below it. See picture below and how it disperses the load.

Rough opening framing

So, between your 3 windows are a crippler, king, king, crippler and are there to support the structure. Hopefully, this answers your question.

FYI - What the diagram calls jack studs, I know as cripplers.