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Cost guide: electricians

We asked an expert electrician about how to avoid extra costs and save money on three common household electrical jobs.

RCD fault resulting in circuits tripping and power loss

About the job

An RCD (residual current device) fault is the most common reason for power loss,” says Ben Mitton, an electrician from Dave Mitton Electrical Ltd in Loughborough. “Lots of things can cause the fault, so it’s important, for both safety and cost reasons, to hire a skilled electrician.”

What adds expense?

“As the fault can be occur because of an appliance or the wiring, the electrician has to follow a methodical process to find the cause. This takes time,” says Ben.

“If you don’t investigate the cause yourself, by unplugging all appliances and then trying each one in turn, your electrician will waste time testing the appliances first.”

How can I make it cheaper?

“The electrician will need access to the distribution board (fuse board) and may need to go into all the of rooms, possibly including the loft,” says Ben.

Make sure access to these areas is clear, so that the electrician can work quickly when they arrive.

It’s very difficult to quote for fault-finding as the electrician won’t know how long the job will take, but always check the hourly charge before work begins.”

Distribution board upgrade

About the job

Having a modern distribution board fitted with a minimum of two RCDs provides safety and control. An RCD will switch off the electricity in a fraction of a second if you get an electric shock. It will also ‘trip-out’ if you have faulty appliances – reducing the risk of fire.

What adds expense?

Ben says: “Most modern distribution boards will have two RCDs controlling the circuits. Alternatively, at extra cost, you can have all of the circuits controlled by individual RCDs (RCBOs). This gives you greater control if a fault occurs as it will only affect one circuit.”

How can I make it cheaper?

“Once the electrician has replaced the distribution board, a series of tests must be carried out,” explains Ben. “The electrician will need to access all areas of the property to carry out the checks. Prepare for the arrival of the electrician by making sure access is available so that the job can be carried out quickly.”


Once the distribution board upgrade is complete, the electrician should issue you with an Electrical Installation Certificate and register the work with the building control department of your local council.

Full rewire of dwelling

About the job

“Common reasons for rewiring a house include outdated cables – a lack of earth wires and rubber or lead sheathed cables,” says Ben.

What adds expense?

“During a rewire, the electrician will need access to every room, the roof and under the floors,” says Ben. “If the occupants live in the house while this is going on, the electrician will need to spend time making the house clean and habitable at the end of each day. This can add considerable time and expense to the job.”

How can I make it cheaper?

“A full rewire of a three-bedroom house which is occupied takes around one week to complete,” says Ben. “If the family can go elsewhere while the rewiring work is undertaken, this can significantly reduce the time required.”

Ben advises "Don’t underestimate how messy a rewire can be. There will be a lot of dust. Look for an electrician who is conscientious and insist on dust sheets and vacuuming up at the end of the day."

Find a Which? Trusted trader electrician in your local area.

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