An extra room does not need to have been specially built, but your home will not qualify for a reduction unless the room is essential or of major importance to the disabled person.
Nid oes rhaid bod ystafell ychwanegol wedi'i hadeiladu'n arbennig, ond ni fydd eich cartref yn gymwys ar gyfer gostyngiad oni bai bod yr ystafell yn hanfodol neu'n bwysig iawn i'r person anabl.