I am drawing the opening for floor plan. I wonder should the highlighted in blue have walls? Thank you for your help.
I think you should take a course in reading plan documents such as this. There is a ton of information presented in the drawing. Since it’s a 2D drawing instead of a 3D model, it shows some objects that are hidden. It may be important to add those details in the 3D model but it depends on what and where they are. Remember you are creating in 3D so think in 3D.
It looks as if the broken lines may represent beams which have presumably been shown because there are no walls to carry structure above.
So I would think the answer is no. But, as has been pointed out, you need to understand the 2D drawing to create a 3D one. So knowing what BBFM stands for would be a good start.
And, again, local drawing conventions vary. To me it seems that here the dashed lines stand for things that are above the “cut plane” of the drawing while the less dense (or are they dashdot) rectangles might be things like foundations that are below the floor. Here in Finland that would be the other way round. The long dash - short dash lines are probably beam centerlines.
BBFM might stand for Beam By Floor Manufacturer. But we are guessing.
What I think can safely be inferred is that walls are traditionally shown with a heavy outline and there aren’t any of those inside the blue lassos.
Agree with Annsi (here in US). It looks like there are two posts. and no other walls there on the lower level. The area under all the stairs are open besides the walls on the right–without further information that is. It appears the stairs continue upward on the right. So there is another intermediate landing there. I think the beams shown there are at the landing level. The upper floor plan should help clarify the floor opening, but it looks like a large rectangle bounding all of the stairs.
Frankly I’ve never seen this nomenclature but do you think BBFM(-4R) is a beam four risers down from the main floor?
Aren’t you glad so many authorities insist on 2D drawings instead of 3D models?
Is what I had figured the broken lines are is a railing like everyone said you need to understand the 2d drawing. I am 95% sure that is what the circled area is.