Can I do it myself, or does the law require a registered tradesperson?

Restricted electrical works in a home may only be carried out by a Registered Electrical Contractor on the Safe Electric register, the scheme the Commission for Regulation of Utilities appoints under section 9D. Doing them unregistered is an offence under section 9E, with fines of up to 5,000 euro on summary conviction and up to 15,000 euro on indictment. Restricted works include important domestic electrical jobs: new installations, work on the distribution board, new or replaced circuits, work in special locations such as bathrooms, and the inspection and certification of existing installations. There is no homeowner exemption: the restriction has no for-reward element, so rewiring your own house or adding a circuit yourself is inside the offence. What the law leaves open is the minor works list in regulation 4(3): replacing an accessory such as a light switch, replacing or relocating a light fitting on the existing circuit, and adding a socket to an existing radial circuit.

Gas works on domestic fittings, installing, repairing, servicing, maintaining or replacing them, natural gas and LPG alike, may only be carried out by a Registered Gas Installer under section 9G, on the register the Commission for Regulation of Utilities has appointed a supervisory body to run. Unregistered gas work is an offence with fines of up to 5,000 euro on summary conviction and up to 15,000 euro on indictment, and that includes boiler servicing and appliance repair. There is effectively no legal DIY gas work on fixed domestic fittings. The carve-out that matters to a homeowner is work specifically designed to be done without a tool, such as clipping a regulator onto a cylinder or connecting a flexible cylinder connector without fixed pipework. Everything with fixed pipework or an appliance behind it needs a Registered Gas Installer.

For builders, the Regulation of Providers of Building Works Act 2022 created a statutory register, but the registration obligation and its offences have not yet been commenced, so it does not currently require builders to register. This guide does not identify a separate national statutory registration requirement for plumbing that does not touch gas, roofing or the other trades.

Registered Electrical Contractors must issue a completion certificate for all but minor works, and you keep the original white copy. If unregistered work has already happened, the law's route is an inspection arranged through the supervisory body, which can certify work that meets the safety rules. A Registered Gas Installer must issue a completion certificate for all gas works: a Declaration of Conformance, with the original white copy handed to you immediately on completion. Every registered installer also carries an annually renewed photo ID card with a registration number.