In 1975 the bar was extended and the reception area improved. By 1977 the need for further expansion was evident and in a two stage development, an additional forty bedrooms were added - all with ensuite bathrooms.
A new dining room was also constructed with doors leading onto a patio where dining could be enjoyed outdoors during the summer time. The lands and woods surrounding the hotel were landscaped and have since provided pleasant walks for hotel guests.
1999 saw major investment and upgrading of the hotel and its facilities. A superb new Leisure Club was added comprising of an 18 meter deck level swimming pool, jacuzzi, sauna, steam room, gymnasium and an aerobics studio. Included in this redevelopment also was the addition of the Health and Beauty Salon and renovations took place in the public and conference areas with the addition of a new meeting room and a boardroom. The hotel was relaunched as The Ardilaun House Hotel, Conference Centre and Leisure Club.
The Ardilaun now had 89 bedrooms to include a number of suites. The hotel is rated four star and owners, management and staff are very proud to provide this level of service in the dining-room, accommodation and public areas.
In 2005 a further redevelopment commenced which reached completion in 2006. This exciting programme saw 36 luxury new rooms, 2 tiers of underground parking, conversion for 4 existing bedrooms to Garden Suites, extensions to the Restaurant, Bar, foyer and Connacht Suite ballroom and grounds were fully landscaped.