Swapping wood beam / joist for metal possible Party wall ?

Hi
I'm looking to convert my attic, and as part of it I am replacing the wood beams over my windows / bays with steel, then attaching / fixing the ceiling / floor joists to these.

I've had a few different builders in, all with differing thoughts and ideas, so over to here.

The photos below show the front bay 1st floor. I wish to replace the beam above it for strength.
My question is how to do this as it looks like it sits on the party wall.
What questions should I ask the builder, what issues would I have etc.

It looks like the beam sits on the party wall, but also on the angled bricks, which has another smaller beam sandwiched in them (I think these bricks don't take much if any weight)
If my beam sits/overlaps the party wall does this pic show the neighbours one?

Thanks

compact said:

The photos below show the front bay 1st floor. I wish to replace the beam above it for strength.

Click to expand...

Why? What qualifies you to make the assumption replacing? It doesn't look structurally unsafe to me imho.

Nothing qualifies me (hence asking on here), I've just been going on the advice from builders etc.
So are you saying I could attach joist hangers to that beam for my the new floor joists of the attic?
What size beam should it be to take the weight of the new floor?

Why not just ask your SE, you'll more than likely need one anyway if you're doing a bona fide loft conversion.

As above suggests, you will need a view, at least, from a SE.

There are too many unknowns ref. total proposal, point loads, tieing-in the bay and party wall issues.

It's a straightforward job, but most builders would require a drawing, and you would be better off for peace of mind, and future sale prospects, in having BCO involved.

I'd suggest that you dont do any more demo, and, unless you have some experience, not to attempt the job yourself.