Around three quarters of homes in the UK have mains gas central heating. It's currently the most viable and cost-effective option for many homes but is responsible for a large part of your carbon footprint.
Gas central heating is a 'wet system', which means a gas-fired boiler heats water to provide central heating through radiators and hot water from your taps.
If you need to replace your current gas boiler, it's worth making sure that your new system is as efficient as possible. Plus it's a good time to improve the energy efficiency of your home to help keep it cosy and your bills in check.
If you're not connected to the gas grid, the following are also 'wet systems' which work in a similar way, but burn a different fuel:
If you're installing a new gas heating system, factor-in both the costs of installing it and gas use to heat your home. If you're replacing your boiler, you'll already have radiators and pipework, though some may need upgrading.
A new gas boiler can cost between £400 and several thousand pounds, depending on the type, brand and size.
Plus you'll need to pay for installation and any extras such as a system clean. If pipework needs changing, or you're moving the location of your boiler it will add to the cost.
Gas is around a quarter of the price of electricity per unit (or kilowatt hour). However wholesale gas prices are increasing so it's likely to cost you more over the coming year.
For an average home, it can cost around £500 per year for gas heating and hot water.*
That's a rough guide. Your actual heating bill will be affected by:
Boiler efficiency is particularly important. Replacing an old G-rated gas boiler with a modern A-rated boiler with a full set of heating controls could save you between £45 and £300 per year (according to the Energy Saving Trust).
*(The estimated cost of heating and hot water using gas is calculated using the average annual heat demand for a medium user (12,000 kWh) from Ofgem, and the price per kWh for gas according to the price cap, calculated by Which? in October 2021.)
From 2025 there will be a ban on installing gas boilers in new build homes.
There are no plans yet to ban replacement gas boilers in existing homes. The government has said that it plans to phase- out the installation of gas boilers beyond 2035. But it will respect consumer choice so no one will have to rip out their existing boiler before the end of its life.
But to reach net zero in the UK by 2050, we'll have to cut gas use.
Alternative heating systems to consider to future-proof your home include:
Heating is responsible for almost a third of the UK's greenhouse gas emissions, according to the Committee on Climate Change.
Some energy suppliers sell green gas. This is produced when organic materials are broken down, or from landfill gas.
It releases the same emissions when burnt but can be considered carbon neutral because it doesn't add more CO2 to the atmosphere overall (as it's made from organic materials that absorbed carbon dioxide as they grew).