Alison:
The 1901 and 1911 census records won't help with identifying a house and there are no maps associated wiith the censuses.
What you need would be the cancelled valuation books which show the changes in property ownership from 1856 to 1900+. See the link below for background. Right now for the Republic, these books are not online but hopefully will be in the future. The books are online for the six counties in Northern Ireland. Go to the PRONI web site to see examples.
http://www.irish-genealogy-toolkit.com/revision-books.html
www.askabout ireland.ie has the Griffiths and can show you which plot was leased by Patrick Kneafsey. You can then use other maps to see the property today.
I assume the cancelled valuation books are in the National Library. Also, the Mormon Church has microfilmed the books and you can likely order the film through them.
Roger