The short answer
Anything involving gas requires Gas Safe registration by law. Most electrical work in kitchens, bathrooms and outdoors is notifiable under Part P. Structural alterations need building control.
- Gas. Any work on a gas appliance, pipe or flue must be done by a Gas Safe registered engineer. This is criminal law, not guidance, and it applies to your own home.
- Electrics. In England and Wales, new circuits, consumer unit work and most work in a bathroom or outdoors is notifiable under Part P and must be certified. Replacing a like for like socket or light fitting on an existing circuit is not.
- Structure. Removing or altering a load-bearing wall, beams and anything affecting foundations needs building regulations approval.
- Asbestos. Common in artex, older floor tiles, soffits and garage roofs. Do not sand, drill or break it. Get it tested.
What will ruin it
Uncertified work surfaces when you sell the house, when you claim on insurance, and when something goes wrong. A missing certificate can stall a sale for weeks.
Why it works
These rules exist because the failure modes are carbon monoxide poisoning, electrocution and collapse, none of which give much warning to the person who did the work.
Gas work requires Gas Safe registration by law and most electrical work is notifiable. Where a tip says to call somebody, that is the advice. Full disclaimer.
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