Main DB @ GF then one sub DB @ 1F so you only need to korek one hole (single tree trunk between GF & 1F) rather than a huge hole for 20-40 wires returning to GF

It will involve rewiring of the first floor circuits (lights, sockets, and water heater) to point back to a sub DB box on the first floor (1F).



A check is best to ascertain the feasibility; putting in a sub DB is recommended for high ceiling/larger houses so that you won't need a lot of redundant runs back to main DB at the GF.

But first and foremost I would do a check on the existing cables, sockets, water heater related to ascertain the health and whether the existing DB box and wiring is up to code.

This is because houses built >30 years ago don't necessarily follow current standards, ELCB was used and they were so insensitive that they're only good for fire protection (does not save lives), and due to old age the old ELCB/RCD failed to trip.



If you're in Klang Valley/Selangor area, do PM me for further discussion.

This post has been edited by ceo684: Jul 6 2025, 03:53 PM