Employing singles just just isn't likely to happen inside a domestic problem, it would be perfect for conduit down the walls but an absolute nightmare to operate the remainder of it in conduit less than floorboards etc. For 6mm2 T&E, I would possible use individual 20mm oval conduits, 1 for https://ovalconduit01123.aboutyoublog.com/30062196/round-conduits-for-dummies