Water-based underfloor heating and your boiler
A water-based underfloor heating system runs off the boiler via a manifold, usually at a lower flow temperature than radiators, and needs the floor buildup to accommodate the pipework. It's often more efficient paired with a heat pump than a gas boiler, because of that lower operating temperature.
Why Gas Safe registration is a legal requirement
Anyone installing, servicing or repairing a gas appliance or gas pipework in the UK must by law be on the Gas Safe Register, which replaced CORGI in 2009. This covers boilers, gas fires and gas cookers. Using an unregistered engineer for gas work isn't just risky, it's illegal, and any resulting certificate isn't valid.
First fix and second fix heating work
On a new build or extension, "first fix" is running pipework to radiator and boiler positions before walls are closed up; "second fix" is fitting radiators, thermostats and the boiler itself once decorating is done. Getting boiler flue routing agreed early avoids conflicts with other trades later.
Background checks and identity verification
Every Gas Safe registered engineer has an ID card with their registration number and the specific categories of gas work they're licensed for — ask to see it, and you can also check a registration number directly on the Gas Safe Register website before booking.
Heating emergencies — what to do
If you smell gas, don't use any electrical switches, don't light a flame, turn off the gas supply at the meter if it's safe to reach, and call the National Gas Emergency Service on 0800 111 999 before calling a heating engineer. For no heat or hot water without a gas smell, check the boiler pressure and any error code before assuming a full breakdown.
When to replace vs keep existing radiators
Radiators themselves rarely need replacing unless damaged, corroded, or you're changing the property's heat demand (e.g. adding a heat pump, which often needs larger radiators to run at a lower temperature). A power flush can often extend a radiator's working life significantly cheaper than replacement.
Gas safety duties for landlords
Landlords must have a valid Gas Safety Certificate (CP12) renewed every 12 months for any gas appliance in a rented property, and provide a copy to tenants. It's a legal requirement, and letting agents/insurers routinely check for it — failing to have one can invalidate insurance and result in prosecution.
Gas fires and stoves — same Gas Safe rule applies
Installing or servicing a gas fire, gas stove, or gas oven/hob is gas work under the same legal framework as a boiler — it must be done by a Gas Safe registered engineer qualified in that specific appliance category, not just any gas-qualified engineer, since categories are appliance-specific.