Central Heating System Costs

How much should central heating cost?

Unfortunately, there is no easy answer to this question, the total cost will depend on the size of the property, the type of system currently installed, whether you are replacing like-for-like, the amount of new pipework needed, the number of radiators required, whether you are installing underfloor heating and more.

However, as a rough guide, replacing a regular boiler with a modern combi boiler powered system in an average-sized post-war, three-bedroom home should cost between £1,500 – £4,000. But this still represents a difference of £2500. To understand the costs further we need to break down the installation into its individual components.

The components of a central heating system

Gas and oil-fired central heating systems consist of three main elements. Let’s look at these in more detail and discuss the cost of each individually.

Boiler

The boiler is the heart of your central heating system and it typically represents the majority of the replacement cost. There are many types of boiler available today, including regular boilers, combi boilers and system boilers. We will cover these in more detail later on.

But in our example, we chose a combi boiler which is a modern efficient gas boiler capable of providing on-demand hot water. A boiler like this typically costs between £1,500 – £1,800 depending on the output. This represents around 60% of the total boiler installation costs.

Radiators

You may need to replace your radiators along with the boiler, especially if they are old and leaking. Radiator costs vary depending on the style and finish but as a guide, standard radiators cost from £150 – £250. You will then need to factor in installation costs on top.

Heating engineers typically charge a day rate for individual radiator installation of around £300 per day for a two-man team. But for complete central heating installations, most heating engineers will provide you with an all-in price for the job. In our three-bedroom home example, we would expect to pay around £1,000 – £1,200 for six radiators.

Pipework

If the boiler is the heart of your system, the pipework is the veins. The pipes take hot water from the boiler and feed it to the radiators. Good quality pipework is essential if your system is to work efficiently. Pipework can be either plastic or copper, we recommend copper if your budget allows because it will last much longer.

There are several methods for installing pipework, including Feed and Return, Single Pipe Loop and Microbore. Your heating engineer should be able to provide more information about the most appropriate type for your home. In our example, we’ll use a standard Feed and Return system which should cost between £800 – £1000.

Now you know the different factors that make up the cost of installing a new central heating system. You can make a more informed judgement about which components you need. However, by far the most important of these is the boiler itself. Ultimately, this will determine the overall cost and efficiency of the overall system.

So it’s important that you choose the right type of boiler for both your home and budget. So let’s look at the different types of boiler technology available and how they may affect costs.

Types of central heating boilers

Regular boilers

Regular boilers heat cold water stored in a water tank, before feeding it into a hot water cylinder for storage until use. This is a traditional type of boiler which most post-war built homes had installed as standard. This technology is somewhat dated, however, and they are not the most efficient choice. So while installation costs are low, (if you are replacing an existing regular boiler) running costs are quite high compared to other boiler types.

Estimated installation costs: £1,750 – £2,200

Combi boilers

Combi boilers (combination boilers) are all-in-one units which take cold water directly from the mains and heat it on demand. This means there is no need for a separate feed tank or a hot water cylinder. Because combi’s heat water on demand they are one of the most economical boilers for mains gas. They are also cost-effective to install because there is no need for a separate water tank or cylinder.

Estimated installation costs: £2,000 – £3,600

Read our Best Gas Combi Boilers Guide for more information on our recommended best buys.

System boilers

System boilers work in the same way as regular boilers in that they heat the water before storing it in a vented hot water cylinder. System boilers, however, take water directly from the mains so there is no need for a separate feed tank. The advantage of this type of boiler is that they have higher water pressure and can supply large quantities of hot water in one go. This makes them suitable for larger properties with lots of bathrooms.

Estimated installation costs: £2,000 – £4,600

LPG boilers

LPG (Liquid Petroleum Gas) boilers are typically installed in small to medium-sized properties which are not connected to the mains gas supply. Installation costs for this type of boiler vary depending on how much infrastructure already exists. If you are installing one from scratch you will need to factor in costs such as the LPG storage tank and connecting pipework.

Estimated installation costs: £2,500 – £6,000

Heating oil boilers

Heating oil boilers are another option for homes not connected to mains gas. They are more expensive to buy than LPG boilers, but they work more efficiently (typically 90-95%). This makes them suitable for larger remote properties. Similar to LPG boilers the cost of installation depends on how much infrastructure already exists. A separate storage tank, for example, can cost between £700 – £900.

Estimated installation costs: £3,500 – £8,000

Central heating boiler prices

When it comes to central heating boilers there is a wide choice of technologies available which vary in price dramatically. But the cost of installation itself often makes up more than half of the total cost. The actual cost of installation varies depending on the type of boiler currently installed and the technology you are replacing it with.

The most cost-effective installation involves replacing like-for-like technology. For example, replacing an existing combi-boiler with an updated model. But this is not always possible, as most people are replacing a boiler which uses outdated technology. In this case, the boiler may have to be relocated which will require extra labour and pipework.

Other costs to consider

When installing a new boiler you should also factor in other costs such as heating controls, system balancing and flushing. Most boiler manufacturers require that existing systems are flushed before replacing the boiler. This is to remove any sludge, rust and debris which may damage the new boiler. The cost of this varies according to the size of your system but expect to pay between £200 – £500.

Smart Heating Controls and TRVs (Thermostatic Radiator Valves) are also worth considering because they will help to reduce your ongoing energy bills. The cost of installing these systems will depend on how sophisticated the system is and the number of radiators installed. Expect to pay up to £20 per radiator for a TRV and anything from £250 – £500 for a smart thermostat.

You’ll also want to take a look at boiler warranties, these will help safeguard your boiler and its usage long term. Most manufacturers will provide a 1-10 year warranty as standard, but some will offer more at an extra cost.

Read our Boiler Warranty Guide for more information.

Financial support available

Whether you are replacing an existing boiler or installing a system from scratch, the cost of installation can be prohibitively expensive. Fortunately, the government has several programs available to help reduce costs.

ECO Scheme

Under the ECO scheme, qualifying homeowners could have their old old in-efficient boiler replaced FREE of charge. To qualify your existing boiler must be 8+ years old and the homeowner will need to receive certain benefits.

Read our Government Boiler Grants Article for more information.

Green Homes Grant Scheme

The Green Homes Grant scheme was launched in September 2020 and provides up to £5,000 for homeowners to make certain energy-efficient improvements to their home. While boilers are not specifically covered you may be able to claim for ancillary devices such as smart heating controls which will improve the efficiency of your system.

You can find out more information about the Green Homes Grant scheme on the Energy Saving Trust website(opens in new window).