The just and reasonable split between the residential part and the non-residential part is 1/5 for the residential part and 4/5 for the non-residential part.
Y rhaniad teg a rhesymol rhwng y rhan breswyl a'r rhan amhreswyl yw 1/5 ar gyfer y rhan breswyl a 4/5 ar gyfer y rhan amhreswyl.