Cavity Wall Insulation Electrical Requirements

Prior to Just Rite commencing with their insulation work, we are obliged to check the existing cabling and circuit protection to ensure the electrical systems integrity is not compromised after the installation of insulation is complete.

To do this, the electrician conducts a quick inspection of the switchboard and will determine the correct course of action required to ensure that the work can be carried out safely, as well as ensuring that the existing cabling will be able to withstand the increase in temperature that will occur after the insulation is installed.

Generally, there are a few options to maintain the cables integrity, and these are listed in the estimate provided. Below are explanations for the work suggested in the estimate you will receive from the electrician.

RCD - 13A Power circuit protection installation for cavity wall insulation
This work is required on all power circuits when the existing cabling is rated at 75 degrees.
13A RCD’s (safety switch) are installed to ensure the cable will not reach 75 degrees when loads are applied to the circuit.

RCD - 16A Power circuit protection installation for cavity wall insulation
This work is required on all power circuits when the existing cabling is rated at 90 degrees and is usually only present in houses built after 2006, but not limited to as V75 cable is still available to install. 16A RCD’s (safety switch) are installed to ensure the cable will not reach 90 degrees when loads are applied to the circuit

16A circuit to kitchen area with a new cable to reduce overcorrect issues
Depending on the loads applied to the power circuits within the house, overcorrect problems may occur when too many appliances are connected to the circuit. Over-current problems may be amplified when 13A RCDs are installed. This work is not compulsory for Just-rite to complete their work, but it is advised in order to reduce the circuit constantly tripping when appliances are used. A new v90 is installed and is recommended that this new circuit is installed in the kitchen area, as loads in this area are usually the greatest in the house. The work involves splitting the kitchen from its existing cabling and connecting it to its own 16A RCD at the switchboard.

In some instances, a full switchboard upgrade is required. This is generally needed when the switchboard is very old, and new switchgear cannot be adapted to fit on the existing board. This includes boards that have ceramic fuses holders installed and boards with “Quicklag” circuit breakers (these are large black switches). When this is required, there are a few things that must be present to comply with current electrical safety standards (AS3000). Namely, these are an electrical earth stake and new main earth cabling, and the Main switch, used to isolate all circuits in case of an emergency. The entire electrical system is then tested for faults, and any faults existing must be cleared for the new board to operate safely. Any faults resulting from poor “backyard handyman” installations or any actions outside of the electrician's control will be rectified at the owner's cost.

swithboard ceramic fuse