Thanks very much for all your advice guys. I don't know what I'd do without your support. Before I go for the pump option, I want to eliminate every possibility and your expert advise is crucial.
I think you guys are right that the water is finding it's way down a hill/driveway at the side of the house and entering into a gap within the footing stones at the lower end of the property. The landscape at the rear of my house is higher, so it's possible it's coming down from there...How can I be sure?
One option I was thinking of is to dig down outside where the water is entering from and somehow seal it with concrete or some tanking membrane???
Anyway, as promised, it took me a bit of time, but below are diagrams of the house.
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