The current trend is to re-use the house as opposed to generate vast tracts of space. This usually involves internal remodelling to open up and / or combine rooms, together with a modest extension and development of hinterland to the rear into somethign usable. The use of almost detached elements and low key detailing couple with primal materials like timber and steel completes the palette.
Donaghy and Dimond do fine work in this field, not immediately apparent from their website
http://www.donaghydimond.ie/
I visited two houses they did last year with the AAI and they were quite stunning in their simplicity and appropriateness.
http://architecturalassociation.ie/
[broken link removed]
ODOS Architects are another kettle of fish, but their Castlewood extension may interest you:
[broken link removed]
Finally there is Box Architects
http://www.box.ie/projects/index.html
Have fun learning to navigate their site.
These are three of the best out there are the moment in my humble opinion. My plugs don't fit the stuff they do, me being far more geared to traditional design, but there is no doubt they ring the changes very well and their work looks finished to a very high standard. No connection with any of them, except I know the father of one of the ODOS guys who was a lecturer Bolton St DIT and for whom I worked at one time. I have never met his son.
A point I've made to many another correspondent here is not to limit yourself to a geographical location for your architect's practice. He/she could be on the Aran Islands if he was the right person for the job. The fact is that many of the best architects live and work in Dublin. Some may even have cars.
ONQ.
[broken link removed]