Central heating isn’t something we tend to think about most of the time. When it’s cold we turn up the thermostat; when we’re too warm we turn it back down.
But if it’s broken or the temperature in your house doesn’t feel right; then you tend to notice.
There are many reasons why you might need to install new central heating. Your system might be old and inefficient, your boiler damaged, you are renovating your home, or you’ve bought a new house and there is no central heating installed.
If any of these apply to you then you’ll want to know what the best options are for fitting a new heating system. In this article we’ve provided a detailed guide of everything you need to consider when installing central heating: what items you need, how much they will cost, and how long they will take to install.
How much does it cost to install central heating?
As with the cost of most services, the answer to this question depends on a number of factors. The make and model of boiler you buy, number of radiators needed, length of pipework, type of heating control and the amount of work involved in the installation, will all affect the total cost.
For an average 3 bedroom house we estimate that materials, installation and cost of labour will be between £3,000 – £4,500
|Work required (item and installation)||Estimated cost|
|Boiler||£1,000 – £2,500|
|Radiators x 9||£1,000 – £1,300|
|Pipework||£800 – £1,000|
|Water tank (if required)||£200|
|Total cost||£3,000 – £5,000|
We’ll breakdown the cost of these in more detail, as well as covering what is involved in installing central heating and how long you can expect it to take.
Central heating cost breakdown
There are lots of choices when it comes to boilers and a few decisions you’ll have to make to narrow them down. What type of fuel supply you have, what system is currently in place, the size of boiler and how much hot water is required, will all inform which boiler will be most suitable for you.
Unsure what type of boiler you need? Let’s look at the options.
The type of fuel supply you have will narrow down what type of boiler you can get. Most boilers you find in homes today run off natural gas. It comes in through pipes and the big benefit is that it is available whenever it is needed.
If your home isn’t connected to a gas network then you might be best looking at a boiler that runs off oil or LPG. You will need to install a storage tank outside your property which is filled with your fuel source. Typically, this would need to be re-filled once or twice a year, depending on the size of the tank and level of consumption.
For flats or smaller homes, with less demand for hot water and central heating, electric boilers can often be a good choice. They don’t produce emissions and are very quiet but the costs to run can be higher. On average, electricity costs 17p/kWh vs 4p/kWh., so you may be paying as much as four times the cost to run your heating.
If you want a boiler that is more environmentally friendly, you could consider a biomass boiler. These are more expensive to buy, ranging from £5,000 for a hand fed boiler, up to £20,000 for an automatic fed pellet boiler, but often cheaper to run – especially if you have your own fuel source to keep it going.
After deciding what fuel supply you are going to use you need to decide on the type of boiler.
Types of boiler
Three main types of boiler: combi, system and regular.
A combi boiler, or combination boiler, is a single unit that heats both hot water and central heating. As it is connected to the mains water, there is no need to have a hot water cylinder or a cold water storage tank in the loft. This frees up space in your home and often makes the price of installation cheaper as you don’t need to pay for a tank or the pipework. Combi boilers are also very energy efficient as they only heat up water when you need it.
If you have a large home, or a house with lots of bathrooms, then a combi boiler might not be the best choice. Turning on lots of taps or running more than one shower will cause the water pressure to drop and it may struggle with the demand.
Cost: £500 – £3,500
A system boiler is still connected to the mains water, which it uses to provide central heating, but it also has a cylinder for storing hot water (there is no need for a water tank in the loft). System boilers have a fast response time and can heat multiple taps or showers at once, but you are limited by the size of the cylinder. As soon as the water runs you have to wait for it to heat back up.
Cost: £900 – £2,750
A regular boiler, also called a conventional or heat only boiler, requires two tanks in the loft: a cold water storage tank and a feed tank to maintain water; and a hot water cylinder positioned somewhere in a room under the tank . Although regular boilers take up more space in your house, they are usually the best choice if you need to heat up a large amount of water at once.
Cost: £900 – £2,500
Choosing the size of boiler
When we talk about boiler size we are not referring to the physical height or width: it relates instead to how much power it can generate. The size of a boiler is its output in kilowatts (kW), and typically the ‘bigger’ the boiler, the more heat and hot water it can supply. Combi boilers tend to have higher kW outputs as they need to instantly heat water when it is required, whereas system and regular boilers heat water over a slower period of time.
You may think that getting the biggest boiler available will be best but this isn’t the case. A boiler that is over-sized can result in reduced efficiency and cost more to run, as it takes longer to warm back up after it has cooled.
Choosing a boiler that is too small can also cause problems. If you need more hot water or central heating than the boiler can supply then you may find yourself standing under a cold shower or shivering in a chilly house.
For the average 3 bedroom house with 9 radiators, a combi boiler with an output of 24-30kW will easily meet the demand. For a larger house with more radiators and more bathrooms, you will likely need a boiler with a size of 35kW.
To work out out what size boiler you need, add up the number of radiators and bathrooms you have in your house. Then use our boiler size calculator to see which is best for you.
Once you’ve narrowed down your choices by type and size you can focus on the make and model of your boiler.
Brands of boiler
The brands of boiler vary in price depending on quality of product, reputation, ease of service, length of warranty and specification. It might be tempting to spend slightly less but it could cost you more in the long run if you are constantly calling out an engineer to make repairs. Some of the most well-known manufacturers include:
- Worcester Bosch
- Glow Worm.
For an in depth look at the best boilers on the market take a look at our boiler reviews.
Hot water cylinder/cold water storage tank
If you are choosing a combi boiler then you don’t need to factor this in to your cost as it runs solely off mains water.
As we mentioned earlier, if you are choosing a system or regular boiler, then you will need to budget for a water cylinder and possibly a water storage tank.
There are two options for a hot water cylinder: vented and unvented. Both provide hot water but they do so in different ways.
Vented cylinders store and heat water that is supplied from a cold water storage tank in the loft. Vented cylinders are easier to install and are also more common. If you already have a vented cylinder that needs replacing, it will be much simpler and cheaper to get a like for like replacement.
The disadvantage with a vented cylinder is that the gravitational flow of water means the pressure will depend on the height of the tank from the boiler. You may find that the water pressure in bathrooms upstairs is weaker than downstairs, and you need to install a pump to generate extra pressure.
Cost: £500 – £1000 + Cost of cold water storage tank: £200
Unvented cylinders are connected directly to the cold water mains, eliminating the need for a cold storage tank in the loft. The water is heated in a heat exchanger and then pumped to the hot water cylinder, where it stays warm for a few hours until you need it.
Because they are connected to the mains, unvented cylinders tend to provide stronger water pressure and you don’t have to find extra space for a water tank. However, they are more expensive to install and if there is an issue with your mains water then you’ll be without hot water until the issue is fixed.
Cost: £1,000 – £2,000
To calculate how many or the size of radiator you need for each room, we use a BTU measurement. BTU stands for British Thermal Unit and is the amount of energy it takes to heat 1lb of water by 1 degree Fahrenheit. Essentially, it’s a way of working out how much heat a radiator will give out and making sure it is enough to sufficiently heat a room. The larger the room, the higher the BTU needed.
The price of radiators will vary depending on the size and style you buy. Cast iron radiators can cost upwards of £500 each, but for standard central heating radiators you can expect to pay around £100-£150.
If you plan on having underfloor heating then this will cost more than than having radiators. For a 3 bedroom new build house, we estimate the price to be around £3000, and for a renovation around £4,000
The cost of pipework will depend on the size of the house and also the existing layout and boiler system. If the new boiler is not a like for like replacement then it may require more pipework to be installed (especially if you are going from a combi to a regular boiler – with additional pipework needed to connect the hot water cylinder and water tank).
The cost also depends on if there is existing pipework already laid. Installing central heating in a house that doesn’t currently have any could potentially cost thousands of pounds.
For an average 3 bedroom home we expect the cost to be roughly £800-£1,000.
There are lots of choices when it comes to controlling your heating – from wall mounted thermostats to smart sensors. Let’s take a look at what options are available and how much they will cost.
A smart thermostat lets you manage you heating on the move. Controlled through your computer, phone or smartwatch, you can change the temperature or set a schedule even when you’re not at home. It gives you a lot more flexibility but they do come with a higher price tag.
Cost: £150 – £300
Usually fixed to a wall somewhere in the house, a room thermostat will let you turn the heating up or down via a dial or digital display. You’ll also be able to schedule timers for when the heating comes on and turns off.
Cost: £20 – £75
Thermostatic radiator valves (TRV’s)
TRV’s are fitted to the radiators in your house and work by controlling the flow of water through the radiator. If they need to cool a room down they will restrict the amount of water, and to warm a room up they will let more hot water pass through. Combined with a smart thermostat, you can use TRV’s to set different temperatures in each room of the house.
Cost: £10 – £125 per valve
So, there you have a full breakdown of everything you might need to factor in to the cost of installing central heating. But what happens next?
When is the best time to install central heating?
The best time to install central heating is when you can afford not to use it. Obviously having no hot water is going to to be a problem at any time of the year, but, if you can, it’s best to avoid being without central heating during winter. If you have the luxury of planning – we know boilers can break down at any time – then the best time to do this is during the summer months when it is warm.
How long will it take to install central heating?
How long it takes to install central heating will depend on what type of boiler you are putting in, how many radiators need to be fitted, the length of pipework required and if the house is empty or inhabited. An occupied house will usually take longer to complete as the installers need to work around you.
If you plan on installing underfloor heating with a regular boiler (hot water cylinder and water tank) you could be looking at a timeline of around a week, due to the extra work involved. For an average 3 bedroom house it will probably take around 3-5 days to install a new combi boiler, radiators, pipework and heating control.
The best way to reduce the amount of time it takes is to plan ahead and clear any of the rooms an engineer will be working in. This avoids the risk of any accidental damage and also means they aren’t slowed down when moving around.
Installing central heating can be disruptive but engineers will take care to make the process as hassle free as possible. If you’ve bought a house you are renovating then its a good idea to get the central heating installed as early as possible. This avoids the need for any new flooring, carpets or plaster work being disturbed or damaged after you’ve laid it.
Typically, engineers will install a central heating system in this order:
- Fit the radiators
- Lay the pipework that connects the radiators to the boiler
- Connect the heating controls
- Turn off the mains water and gas and install the boiler
- Close the valves on the radiators, fill the system with water, and re-vent the system.
So, there you have it. That’s a full breakdown of what is involved when installing central heating and how much you can expect to pay.