I’m planning to remove part (or potentially all) of an internal stone load-bearing wall. This is roughly 16" deep and composed of what looks like solid stone, although I guess there may be rubble inside (house was built around 1900). The wall supports the upstairs floor joists only. It's not tied in on one side where it meets the stairs and may or may not be tied in with the party wall on the other side - I haven’t removed the plaster to check yet.
Plan A:
Builder tells me it’s best to remove the whole wall up to the joists and use steel goalposts to create a nice big opening. However, given that the wall is so thick and the joists going to the front and back of the house meet here but don’t overlap one another, I’m confused how a relatively narrow I beam would support both sets of joists at once. Is something else needed to broaden the depth of the support (more steel?!).
Plan B:
Would it be better to retain some of the stonework above the opening and use a few 6x4" concrete lintels? Is it difficult to prop irregular stonework? Builder mentioned this method can often result in stones falling away as you create the opening, which I can appreciate with it being old lime mortar. Obviously, in this case I’d have to retain stonework on each side to hold the lintels (say 16” width or so - green on marked up photo below). But I’m wondering how structurally sound these sides would be, particularly if they are both not tied in to the adjacent walls? Added to this, there is a small but significant gap under one of the base stones which looks to have been excavated for plumbing (see photo). I’m concerned that if I were to bring the wall opening back to this point, this stone would be holding more weight and could compromise the structure. Is there any way I could use shuttering and pour concrete in one side to fill the gap and provide some support? What looks like a victorian bitumen damp course has also been disturbed, so I presume I’d need to rectify this too somehow?
Goes without saying that I’m a complete amateur and would seek professional advice and use a builder, but any advice here would be much appreciated.
Cheers
