cameramonkey, there are at least two widely available maps which will help you. The 1837 OS map, and the revision of same around 1847, will provide invaluable information. These are often available at the local county library, but failing that, telephone the Trinity College Map Library, tell them what area you are investigating, make an appointment, drop in, and they'll almost certainly have the exact pages waiting and ready for you to inspect. Free of charge (unless you want to make copies, in which case bring the cheque book).
The house is extremely robust with an appearance of unnecessary weight, making me wonder if it may be early 19th century. If the window glazing patterns are entirely original, the house is no earlier than 1860. If the ground floor sashes are later replacements, the upper floor windows may date to about 1840.
Of course bear in mind that a structure indicated on a map may not be the same structure that is there today. By the very practice of houses being built in advantageous positions, it often made sense when extending or rebuilding to knock the existing house, recyling both the site and the materials. Sustainability in its truest sense.