A little more exploration done and I've picked up 2 of 4' by 6" pre-compressed concrete lintels from the builders merchants. The internal wall continues up into the first floor and up to the stack - there is a small step where the 1st floor joists rest, so it's load-bearing. I've propped above where the lintel is to go and removed a couple of stones. My main problem at the moment is that the stones are large and irregular, so if I remove enough of them to fit a 3' door there will be nothing supporting the lintel. If I can keep the doorway a little slimmer we should be ok.
Think I'm ok using timber props on a stone wall, or is it time to go rent some strongboys?
Think I'm ok using timber props on a stone wall, or is it time to go rent some strongboys?