Rewiring a Flat: Costs, Process, and Signs You Need an Urgent Upgrade
Replacing old electrical wiring is often the most delayed part of a renovation — yet outdated electrics are the leading technical cause of domestic fires. In 2026, a full rewire starts from €952 for a studio flat up to €3,824 for a 5-bedroom property, with chasing channels costing between €5.70 and €8.50 per linear metre and plastering repairs at €7.30 to €10.90 per linear metre. In this article, you will learn when a rewire is essential, the step-by-step process, real-world costs, and common mistakes to avoid.
When is a full rewire essential?
Aluminium wiring is a definitive red flag — common in residential blocks until the late 80s, it is now well beyond its service life. Aluminium creeps at connections, causing joints to loosen, overheat, and arc. If you live in a property built between 1960 and 1990 with original electrics, a rewire isn't a matter of 'if', but 'when'.
Other warning signs include: frequent circuit breaker tripping when using multiple appliances, warm sockets and switches, flickering lights, crackling sounds from junction boxes, and discoloured or scorched sockets. An old consumer unit without an RCD (Residual Current Device) will fail an Electrical Installation Condition Report (EICR), which is required by insurers and mortgage lenders during a sale.
Capacity issues: original circuits were designed for a fraction of today’s demand — induction hobs, ovens, dishwashers, washing machines, dryers, and air conditioning combined require 25A to 32A breakers and dedicated circuits that old fuse boards simply cannot accommodate.
The rewiring process step-by-step
Preparation and chasing
Once the plan is agreed, the electrician marks out cable runs and backbox positions. This is followed by chasing channels for the new wiring — the loudest and messiest phase, which should be notified to neighbours and the building manager. A typical 3-bedroom flat requires 40 to 60 linear metres of chasing, taking 1 to 2 days.
New circuits and consumer unit
Copper CYKY-J cables are pulled through the chases, new backboxes are fitted, and a new consumer unit with RCD protection and SPD (Surge Protection Device) is installed. This is also the ideal time to run FTP cabling for internet and smart home systems — retrofitting cables after plastering means starting the chasing process all over again.
Plastering, inspection, and second fix
Once the circuits are connected and tested, the making good of walls is done using cement mortar, followed by a drying period and decorating. Finally, the electrician fits the sockets, switches, and light fittings, and an inspector issues the EICR — without this, the work is not formally certified.
How much does a rewire cost based on flat size?
The costs for a complete electrical installation and second fix are similar to a new build — for a studio/1-bed €952 to €1,428, a 2-bed €1,139 to €1,709, a 3-bed €1,435 to €2,153, a 4-bed €2,085 to €3,063, and a 5-bed €2,603 to €3,824. For a detailed breakdown of what the installation includes, see our guide on electrical costs by property size.
However, for a renovation, you must factor in chasing and making good, which new builds don't require: chasing channels €5.70 to €8.50/m, plastering repairs €7.30 to €10.90/m, and repainting. In a 3-bed flat, a realistic rewire budget is €2,200 to €3,200 (inc. VAT) including the certificate. You can find a full price list in our construction cost database.
Can you rewire without a full renovation?
Yes, but with compromises. A standalone rewire involves chasing into finished surfaces — once patched, you will need to repair plaster and likely repaint entire walls to avoid visible patches. Therefore, it is most cost-effective to combine a rewire with larger works — during a bathroom renovation or floor replacement, the walls are already accessible, potentially lowering electrical labour costs by 15% to 25%.
Partial rewires (e.g., just the consumer unit or kitchen circuit) are possible as temporary safety fixes, but mixing old aluminium and new copper wiring requires specialized connectors and stricter inspection. In the long term, a full rewire is always more economical.
Common mistakes to avoid
Underestimating the design is the most expensive mistake — too few sockets, missing circuits for future appliances, and no provision for AC or data cables. Adding a single outlet after completion costs €150 to €250, compared to just €30 to €50 during the project.
Plastering over chases before testing circuits is the second mistake — if there is a fault, the walls have to be opened up again. A professional electrician will megger-test all circuits before giving the green light for plastering.
Skipping 'as-built' documentation is the third error — a simple diagram showing where cables run and which breaker controls which circuit saves hundreds of euros during future repairs, DIY drilling, or future inspections. Demand this from your electrician upon handover.
How to approach your rewiring project?
Old wiring is a safety hazard that only worsens with age — and its replacement is the only part of a renovation that is never seen, yet dictates the safety of the entire home. Plan with future-proofing in mind (extra sockets, AC feeds, smart home hubs), coordinate with other trades, and insist on a final inspection report and circuit diagrams.
FAQ - Frequently Asked Questions about Rewiring
How much does it cost to rewire a 3-bedroom flat?
A complete rewire including chasing, making good, and certification in 2026 costs €2,200 to €3,200 (inc. VAT). The electrical installation itself accounts for €1,435 to €2,153.
How long does a rewire take?
In a 2-bed flat, 5 to 8 working days; in a 3-bed flat, 7 to 10 days. You should allow an additional 5 to 7 days for plastering, drying, and painting.
Do I have to replace aluminium wiring?
Aluminium wiring older than 40 years is at the end of its lifespan and poses a fire risk. While regulations might not strictly ban it, inspectors judge it harshly and insurers will scrutinize it in the event of a claim.
Can I live in the flat during a rewire?
Technically yes, but it isn't recommended — chasing creates 2 to 3 days of extreme noise and dust, and the property will be without power for periods. Most clients arrange alternative accommodation for 1 to 2 weeks.
Do I need a certificate after a rewire?
Yes, an electrical certificate (EICR) is mandatory after any major works. Without it, the work is not legally certified, and insurance companies may refuse to pay out for damages.
Calculate the cost of your flat rewire
This overview provides an indicative price range for 2026. The specific cost depends on the size of the property, the number of outlets, and the extent of the chasing required. Before you call an electrician, calculate an estimate using the Numiq online calculator. You’ll get a real sense of market prices, giving you a stronger position when negotiating quotes.
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