I am in the process of removing a load bearing wall to open up the kitchen to the dining room. The house was built in the 1700 in the Cornwall(south England) and is constructed from stone using lime and sand mortar. It is a 2 story house.
I have removed the lath and plaster for the wall that I plan to remove(fig 1). The wall span it will need to support to is 2.4 meters. The supporting wall being removed is on the ground, so the beam needs to support the weight of the second floor. The room dimensions are 2.5m by 3.5 on the kitchen side of the wall and 4.5 by 3.5 on the dining room side of the wall. So I assume the total area the beam needs to support 4.5 X 3.5 + 2.5 X 3.5?
There is a brick wall on side that the beam(fig 2) can rest on. On the other side there is nothing but it does appear to have some concrete foundations(fig 3).
My question is how do I calculate the size of metal I beam or, ideally, oak beam that is needed and are the footings (image below) strong enough to support a vertical beam or do I need to remove them and build new one. Lastly what size/strength of vertical beam do I need to support the weight?
Fig 1
Fig 2
Fig 3