Houses in the Premier County are among the least energy efficient according to the Central Statistics Office.
Roscommon and Leitrim have the least energy efficient standard of housing, according to BER ratings.
The CSO has released the figures, which show 12% of houses in the two counties have a G rating, followed by Tipperary on 11%.
A BER is the Building Energy Rating, which judges the efficiency of a home.
Kildare has the most efficient housing according to BER ratings with 20% getting A ratings.