RBIs who have evidenced capability at this level may work unsupervised on building categories they are registered to work on which may include:
Gall yr RBI sydd wedi dangos tystiolaeth o allu ar y lefel hon weithio heb oruchwyliaeth ar gategorïau adeiladu y maent wedi'u cofrestru i weithio arnynt, a allai gynnwys: