When does your fuse box need replacing?

The fuse box is the least glamorous part of your house. It usually hangs in a storeroom or a basement corridor and gets ignored until something goes wrong. Here is what I look at when I am out on a site visit.

Sign 1: Screw-in fuses

If you still have traditional screw-in fuses (the round porcelain things), the box is probably from before 1990. That means no RCD on most circuits, and no short-circuit protection fast enough for modern electronics. This is the first thing to replace.

Sign 2: Circuits that keep tripping

If the kitchen or living room circuit trips every time you switch on several appliances at once, you either have too few circuits or too small a main fuse. Both are sorted in the same go when we replace the box.

Sign 3: A warm panel or discoloured fuses

Feel the outside of the box after a spell of heavy use. Slightly warm is normal. Burnt, discoloured or smouldering, call us. That is an emergency.

Sign 4: You are planning an electric car, solar or a heat pump

An old box often has neither the space nor the compliant circuits to handle those loads safely. It makes financial sense to replace the box as part of a larger job rather than upgrading piece by piece.

What does it cost?

Replacing a fuse box in a detached house typically runs between NOK 18,000 and 35,000. The variation comes from the number of circuits, whether the main fuse has to be upgraded, and whether the existing wiring can be reused or has to be pulled again. You get an exact price after a site visit.

What does the job include?

• Removal of the old box
• A new box with RCDs and circuit breakers to NEK 400
• Labelling of every circuit
• Function testing of all earth fault and short-circuit protection
• A declaration of conformity, which is what your insurer will actually ask for if something happens

Insurance and regulation go hand in hand here. If you have a fire and the insurer can show the electrical installation was not up to standard, you have a problem. A new fuse box with documentation removes that risk.