This was a decrease from 2011 when Neath Port Talbot had 59.5% of households with three bedrooms and Caerphilly had 59.1%.
Caerdydd oedd â’r gyfran isaf o gartrefi â thair ystafell wely (38.8%, 57,000), i lawr o 40.1% (57,000) yn 2011.