When are gas boilers being phased out and what will replace them?

With events like COP 27 and the Paris Climate Accords taking place on the international stage, it’s no secret that world leaders are on a mission to put a stop to global warming. This is a global effort that is already seeing nations from all four corners of the world coming together to align resources and strategies to reverse the impacts of climate change. The UK is no exception to this rule and has given itself a target to reach net zero carbon emissions by 2050. 

One of the main tactics that the government here in the UK is deploying to make this target achievable is the banning of gas boilers. Over the next 25 years, natural gas-powered central heating systems will be gradually phased out until our homes are all using low-carbon alternatives.

But what will replace them? This article covers everything you need to know about the phasing out of gas boilers and make sure you have all the information about the clean energy alternatives that will take their place. Keep reading to learn how to prepare for the transition when it happens.

Why are gas boilers being phased out?

There are a number of different reasons why gas boilers are being phased out in the UK. Though complex and interconnected, these reasons can be split into two main categories: financial and environmental. 

Environmental

Let’s start by looking at the environmental reasons why gas boilers are being phased out.

Home heating is one of the biggest contributors to global warming in the UK, accounting for an estimated 9.7% of carbon dioxide emissions annually. A large chunk of this comes from the fact that gas boilers produce an average of 2.2 tonnes of CO2 per year.

A gas boiler emits more CO2 than any other boiler type, so it's perhaps no surprise that their removal is key to meeting the zero-carbon target set by the UK government. Combining the emissions of all UK homes equates to twice the emissions of all the country's gas-fired power stations, so the country is looking to reduce and, eventually, stop the installation of gas boilers.

Financial

Turning to the financial, more logistical reasons why there is a push to reduce our reliance on gas-powered boilers, we need to think about the soaring cost of energy that has affected all of us in recent times. Global gas shortages have arisen due to a number of different factors, including the COVID-19 pandemic, the war in Ukraine and frustrated diplomatic relations between the nations that are the main suppliers of natural gas, and these have all led to a situation where energy prices rose by an eye-watering 335% within the space of just one year.

Get more information on surging energy prices.

It’s not just gas boilers that are undergoing this gradual phasing-out process, though. The manufacture and usage of many things that are known to be big producers of greenhouse gas emissions (oil boilers, petrol and diesel cars and heavy goods vehicles, for example) are being restricted as part of the UK’s journey towards net zero. 

When are gas boilers being phased out?

The exact date for when the phasing-out process starts remains unconfirmed, but it looks like the installation of new gas boilers will stop in 2035 for new build homes. The rules will differ for new homes versus pre-existing homes, though, so it’s important to make sure you know exactly what will and won’t apply to your property as things change.

Living in Scotland? Discover everything we know so far about the boiler ban in Scotland.

New homes

2025 will see the start of the government's Future Homes Standard initiative, a list of standards that all new residential buildings must meet. These standards are mostly related to making all new buildings greener. This policy ensures that new homes produce 75-80% less carbon dioxide emissions than new buildings do currently.

The Future Homes Standard states that all new homes must contain low-carbon heating systems, ensuring they will produce fewer emissions. The plan also says that no gas boilers can be installed in new homes, implying that no gas network can be fitted.

However, the government’s Heat and Buildings Strategy, which was released in October 2021, conveyed doubt that this phasing could start in 2025. Instead of doubling down on its proposed 2025 target, it suggested that further review was required to determine whether this was possible.

Update: Please note that as of September 2023, some of the targets set out in the original Future Homes Standard initiative have been pushed back or scrapped altogether. However, the government insists that the commitment to reach net zero carbon emissions by 2050 is still achievable. 

Pre-existing homes

In the same Heat and Buildings Strategy, the government conveyed its ambition to stop new boilers from being installed in pre-existing homes by 2035. 

Instead, low-carbon alternatives to gas boilers will be installed whenever a boiler replacement is required. Again, this cut-off year has only been suggested and has not been made official.

For pre-existing homes with old-style gas or oil boilers, there are already incentive schemes in place to encourage people to ditch their fossil fuel-based heating systems in favour of new, low-carbon alternatives. We’re talking about government-run initiatives like the Boiler Upgrade Scheme that provides upfront financial support packages to help people afford renewable heating systems.

Do I have to replace my gas boiler by 2035?

Let’s cut straight to the chase. No, you don't have to replace your gas boiler by 2035.

Gas boilers already in situ won’t need to be removed and replaced with low-carbon alternatives once the transition process starts as the rules only apply when there is a requirement to install a new boiler. If you have a gas-powered boiler installed in your home, you will be able to use it right up until it needs to be replaced at the end of its lifespan.

These rules will affect new-build properties in the first instance, as they won't have any existing central heating system in place.

It’s worth noting, though, that the government’s current plans are yet to be finalised, with conflicting arguments being put forward on two sides of the picket fence. On the one hand, increasingly cash-strapped homeowners are calling for the outright ban on the sale of gas boilers to be pushed back even further due to the fact that lower carbon alternatives are costly. These calls are being countered by environmental activists who believe that more drastic action needs to be taken to make any kind of impact on the country’s carbon footprint. 

So, whilst the current plans show that you’ll be able to continue to use your gas boiler as normal both during and after the phasing out process, and that you’ll still be able to purchase a new gas boiler up until 2035, it’s highly possible that things could change between now and then. 

What will be the alternative to gas boilers?

There are a number alternatives to gas boilers, some of which are already available to buy or are in the latter stages of development. Let’s take a look at these in a bit more detail, so you have all the information you need to decide which one is right for your home.

Think it might be time for a new boiler? Read our expert guide on how to tell when your boiler is on its way out.

Heat pumps

Heat pumps work by drawing in hot and cold air from an external source, converting this energy, and using it to heat or cool an internal space. There are two main types of heat pumps: ground source heat pumps and air source heat pumps.

Ground source heat pumps

A ground source heat pump utilises the natural heat that is stored underground. It consists of a water pipe network buried underground, outside your home, and an above-ground heat pump. To harness the heat, hot water and anti-freeze are circulated through the pipe network, which absorbs the heat and takes it above ground.

This water and anti-freeze mix is then compressed, and a heat exchanger extracts the heat. This energy is then sent to the heat pump, which supplies your radiators and hot water cylinder with energy.

Air source heat pumps

An air-source heat pump absorbs hot air from outside using a fan. This hot air heats a liquid refrigerant found inside the heat pump and turns it into a gas. This gas is then sent through a compressor, creating more heat energy. Lastly, the hot gas goes through a heat exchanger, where it is used to warm up cool air and water.

This warmed air and water mix is then used in your home heating system while the refrigerant is condensed back into a liquid, and the air source heat pump process starts again.

The pros of heat pumps:

• Although expensive to install, heat pumps could save you money on energy bills if you have a well insulated home, as they produce energy efficiently, and the heat pumps themselves have very low maintenance costs.
• The only power needed for both types of heat pumps is electrical. No fossil fuels are needed for operational purposes, meaning that they are much more environmentally friendly than the likes of a gas boiler.
• Both types of heat pumps offer high durability. Ground source heat pumps can last from 20-25 years, while air source heat pumps last around 20 years.

The cons of heat pumps:

• Heat pumps deliver heat at a lower temperature than an oil or gas boiler. For this reason, you need to have your heat pump running for longer periods to heat your house to the same level as that of a gas boiler.
• You will also require adjustments such as increased size of radiators, as they will not emit as much heat due to the lower water temperature etc.
• You'll need to make space in your garden for either an above-ground heat pump or a condenser unit for both a ground source and an air source heat pump.
• Depending on the current pipework in your home, you may need to upgrade your heating system to prepare for the installation of the heat pump.
• There will be a lot of disruption when installing, including building works and significant pipe runs in some instances.

Heat network systems

A heat network system - sometimes referred to as a district heating system - is effectively one big central heating system that supplies power to numerous buildings via underground insulated pipes.

The heat source could be many things, from waste heat from a shopping centre to geothermal and heat pumps. They are good for the environment as they utilise heat that would otherwise be wasted and can be used to heat several buildings simultaneously.

The pros of heat network systems:

• There is no need for individual boilers in each home with a heat network system. It requires less power to convert heat from one source than lots of different individual boilers. They, therefore, produce fewer greenhouse gas emissions.
• Heat network systems work well in built-up areas, such as city centres.

The cons of heat network systems:

• Requires high installation and maintenance costs.
• Power levels can be inconsistent. Those who rely on heat network systems have often reported periods without hot water.

Electric radiators

Electric radiators are not connected to any main heating supply and work as standalone heating systems. They are filled with either dry elements or thermal fluid, and heat is created through radiation and convection. 

Some people may choose to get a small electric radiator to provide an extra boost to their home’s main boiler-powered radiator system. Note that electric radiators aren’t the same as electric fan heaters, with the latter being considerably less energy efficient.

The pros of electric radiators:

• Electric radiators are relatively efficient, as every energy watt produced is used for heating.
• Easily installed and maintained - you don't need a professional to fit electric radiators, nor do you need one to perform annual checks.
• They provide accurate temperature control and normally come with an easy-to-use thermostat and smart control options.

The cons of electric radiators:

• Electricity is more expensive than gas, meaning higher energy bills.
• As shown in the chart further up the page, the production and distribution of electricity is still a key contributor to the net carbon emissions of the UK. So, whilst your electric radiators don’t generate carbon dioxide whilst they’re running, there is still a considerable amount of CO2 produced elsewhere in order for them to heat your home.

Biomass boilers

Biomass boilers are similar to traditional gas boilers, except instead of gas, they operate on such fuel as wood pellets and chips. The heat generated by the burning of this fuel can heat hot water and provide your central heating system with power.

The pros of biomass boilers:

• Biomass boilers are considered good for the environment as they burn fuel that can easily be replaced. For example, although chopping down trees for fuel is technically bad for the environment, trees can be grown back relatively quickly, whereas it takes thousands of years for the likes of coal to be renewed.
• Wood is a cheap fuel, and its prices will remain steady - unlike gas.

The cons of biomass boilers:

• They tend to be bulky and often require a separate room. You'll also need to consider where to store the fuel.

Solar thermal panels

Like solar panels, solar thermal panels harness the heat energy from the sun, but instead of using it to produce electricity, they are used to create hot water. Used alongside the likes of a heat pump, thermal solar panels can be used to reduce the carbon footprint of your entire home.

The pros of solar thermal panels:

• Have greater efficiency than PV solar panels because the energy doesn't have to be converted into electricity.
• Can work in cold climates.
• Cheaper than PV panels.

The cons of solar thermal panels:

• It can only be used to create hot water.
• High start-up costs.