So house was rebuilt in 1883 effectively 3 storey.
Ground floor, not ours, has two bay windows to the front. One of which has sprung a leak. On inspection our window above the bay has sunk about 7mm and some stonework shifted forward about the same.
Looks like the lintel, apparently it has a special name, is shot.
I feel this ain’t gonna be cheap.

It won’t be cheap – however such work can be good value compared to the cost of internal finishing touches. Although structural it is fairly ‘bricks and mortar’ – and that is fairly straightforward usually.

I say that as someone who put £10k into structural work on our first house, a hangover from bomb damage in the war. It was amazing how much work they did, how quickly it was done, and how long it was signed off for and guaranteed for (100years)

I was quoted about £1,500 for widening an internal doorway on a structural wall (used to be external) Removing and replacing Intel and surrounding brickwork. Just the structural stuff none of the making it look nice stuff.
Guessing yours should be somewhere around that

just make sure the builders support the existing load before removing things – there’s videos of whole houses coming down becasue they were cowboys and hadn’t sufficiently propped the opening first- i.e. dont go for the cheapest quote.

Curisoly, what takes the load if it’s an open bay with no cantilever joists holding the upper floor up (like mine)- the frames cant take the load.??!?

House below had new windows recently ?

Often in old houses the frames were structural.

uPVC replacements rarely are.

Timber bresummers spanning bays are at risk of rot if the roof/flashings of the bay leak.

Curisoly, what takes the load if it’s an open bay with no cantilever joists holding the upper floor up (like mine)- the frames cant take the load.??!?

They build a wooden frame first, using larger timbers then the window frame fixes into that.

Damn it, humming Fleetwood Mac now.

Yep besummer(?) Is gone. Fortunately the guy looking at it is son of the people below. He’s well established and his business is damp/rot repairs.

It shouldn’t be mega money to be honest.
All our windows and door only had soldier course over them. When we needed new windows they insisted (correctly) on proper lintels.
Props up, old lintel out, new one in, replaster.
We had loads of stuff done at the same time, but that bit should only be a couple of days work maybe, three max.
Certainly a pain in the arse though, and unexpected expenditure is always a nightmare.

besummer(?) Is gone.

Bressumer beam

It is the beam across the opening, on which floor or ceiling joists rest and cantilever out to form the top of the bay. They need to also stop the bay from leaning outwards by connecting to the walls and joists solidly.

Our’s had gone in one of our Sheffield houses on a single storey mainly wood bay – I replaced it in a lunchtime with the labourer we had on site. I replaced wood with wood.

That sounds a bit more major repair than a lunchtime if the stonework has shifted 7mm, possibly big cracks hidden somewhere behind a strapped wall
Should it not be a shared cost amongst all the part owners of the building

Had the expert round yesterday.
No dry rot and beam in better nick than he thought. Won’t need replaced just stabilised he reckons the movement is compression of weakened wood but is looking at it from below Monday.
Looks like £1000ish as opposed to £10k