Facebook pixel
new boiler

Get a new boiler

Fixed price boilers, next day

See boiler prices
new air conditioning

Air Conditioning

Get a quote
new heat pump

Heat Pumps

Coming soon

new ev charger

EV Chargers

Get a quote
boiler servicing

Boiler Servicing

Get a quote

Last updated: 5th April, 2024


Boiler Installation London

Boiler Installation London

Key takeaways

  • Boiler installation costs in London average around £2,700 for standard models and can exceed this for more complex setups or high-end systems.
  • Factors like boiler type, property size, and installation complexity impact the total cost and process of boiler installation.
  • Selecting the right installation service entails consideration of energy efficiency, safety compliance, and post-installation support.

Selecting the appropriate boiler for your London home involves understanding the different types available.

As the necessity for modern and efficient home heating systems rises in London, understanding the various aspects of boiler installation is crucial for homeowners. In 2024, the costs and processes associated with fitting a new boiler can be influenced by several factors. 

While the average cost for installing a gas system boiler hovers around £2,700, the price tags can surge for high-end models or intricate installation requirements. The financial commitment includes not only the price of the boiler but also the charges for professional installation services, which encompass labour and materials.

The complexities of the installation process vary, with considerations such as property size, existing infrastructure, and the type of boiler selected playing vital roles. London residents looking to install a combi boiler might encounter different pricing structures compared to those opting for system or heat only boilers. 

Moreover, the quest for increased energy efficiency and adherence to safety regulations adds layers to the decision-making process. Homeowners must be aware of these nuances to make informed choices that align with their requirements and budgets.

Need a new boiler?

Get a quote in 60 seconds, fitted as fast as next day!
0% APR finance available.

Get a quote

Understanding Boiler Types:

Selecting the appropriate boiler for your London home involves understanding the different types available. Each boiler type offers distinct advantages and is suited for specific household needs.

Combi Boilers

Combi boilers, or combination boilers, are the most prevalent type in UK households. These units provide central heating and hot water without the need for a separate water tank. Combi boilers are known for their compact size and efficiency, as they only heat water on demand. Installation costs for combi boilers tend to be lower compared to other types, owing to the absence of additional tanks or cylinders.

  • Typical Cost Range (Installation Included): £1,500 - £4,500

  • Advantages:

    • Space-saving due to no need for separate tanks

    • Hot water is delivered at mains pressure

System Boilers

System boilers require a cylinder for storing hot water, yet they do not demand a water tank in the loft. They are suitable for homes with multiple bathrooms, where the demand for hot water is higher. Unlike combi boilers, system boilers can provide hot water to several taps simultaneously without a reduction in pressure.

  • Typical Cost Range (Installation Included): £1,300 - £3,500

  • Advantages:

    • Consistent water pressure to multiple taps

    • Ideal for larger households with greater hot water needs

Heat Only Boilers

Also referred to as conventional boilers, heat only boilers are typically found in older homes. They require both a hot water cylinder and a cold water tank, usually located in the loft. These boilers are well-matched to systems that include older radiators not designed to cope with the high water pressure delivered by system or combi boilers.

  • Typical Cost Range (Installation Included): £1,800 - £4,500

  • Advantages:

    • Compatible with older heating systems

    • Can supply hot water to multiple outlets simultaneously

Understanding the specifics of each boiler type empowers homeowners to make an informed decision tailored to their household's heating requirements. It's essential to consider not only the initial installation cost but also the long-term energy efficiency and potential savings on utility bills.

London Boiler Installation in-depth Prices Breakdown

Standard Gas Boiler

  • Average Cost: £2,700

  • Key Features: Basic system with a 5-year warranty

Oil System Boiler

  • Estimated Cost: £3,163

  • Considerations: A good option where gas is not available

Upgrading an existing system to a modern, energy-efficient gas boiler ranges widely in price, typically between £1,600 and £2,500, including supply and installation. Factors affecting the cost include the type of boiler, the complexity of the installation, and the rates charged by the installation company.

High-End Models

  • Price Range: £2,500 - £4,500

  • Warranty: Often longer warranties

The Worcester Bosch Greenstar CDI Compact, a compact and efficient model suitable for smaller spaces, is priced at £2,875. It is notable for its energy efficiency and space-saving qualities.

Back Boiler Replacement

  • Cost Span: £2,300 - £6,000

  • Installation Duration: Up to 2 days

Boiler Type

Cost Range



Standard Gas Boiler

£1,600 - £2,500

Up to 5 years

Suitable for most homes

Worcester Bosch 28kW



Compact, efficient design

High-End System Boiler

£2,500 - £4,500


High performance

Back Boiler Replacement

£2,300 - £6,000


More complex installation

The cost for labour and material should be factored into the overall installation price. Moreover, professional installation ensures the safety and efficiency of the boiler, potentially leading to savings on energy bills and extending the appliance's lifespan. Always consult with certified technicians to receive the most accurate quotes for your specific circumstances.

London Combi Boiler Installation Average Costs-

In 2024, Londoners opting for combi boiler installations are encountering a range of costs influenced by factors such as boiler brand, installer, and location. The prices tend to vary significantly across different postcodes.

Most Expensive and Least Expensive London Postcodes-

Most Expensive Postcodes:

Least Expensive Postcodes:

  • More economically priced installations occur in outer boroughs, such as Barking (IG11) or Croydon (CR0).

  • Budget-friendly combi boilers in these areas can be found around the £1,500 mark.

London System & Heat Only Boiler Installation :Averages

In London, the cost of installing system and heat-only boilers varies due to factors like postcode location and installation complexity. Higher-end areas typically command premium prices, both for boilers and installation services.

Most Expensive and Least Expensive London Postcodes

Most Expensive

In prestigious areas such as Kensington (W8) and Chelsea (SW3), boiler installation costs reach the upper echelons. Expect to pay from £3,000 to upwards of £5,000. These prices reflect the premium nature of the properties and the meticulous attention to detail required in such affluent areas.


Average Cost (£)

Kensington (W8)

4,500 - 5,000

Chelsea (SW3)

4,000 - 5,000

Least Expensive

Contrastingly, more affordable boroughs like Barking (IG11) and Croydon (CR0) offer lower installation costs. Here, prices can start as low as £1,500. This can be attributed to the lesser demand for high-end finishes and a more competitive market.


Average Cost (£)

Barking (IG11)

1,500 - 2,000

Croydon (CR0)

1,800 - 2,500

Other Factors Influencing Boiler Installation Cost

When considering the overall cost of boiler installation, several key elements come into play. From the choice of boiler model to the specifics of the property, every factor contributes to the final price.

Boiler Model and Brand

The selection of a boiler model and brand has a notable impact on installation costs. High-end brands like Worcester Bosch pose a greater initial investment, specifically when opting for models such as the Greenstar CDI Compact. However, these are often accompanied by superior energy efficiency ratings.

Boiler Size and Power Output

Boiler size and power output correlate with cost. A larger boiler with a higher kilowatt (kW) rating to accommodate higher demands for hot water and heating will usually be priced higher. For instance, an average 28kW boiler is suitable for a standard London home, yet a more expansive property would warrant a more powerful, and thus more expensive, boiler.

Property Type

The property type influences boiler installation expenses. A compact flat may have limited space, demanding a compact boiler that could be more costly due to advanced design, whereas a traditional terraced house might have more space but could require additional work to fit a new system, increasing labour costs.

Complexity of Installation

The complexity of installation is a crucial determinant of the overall cost. Factors such as the necessity for new pipework or relocation of the existing system, the accessibility of the installation site, and the requirement to remove old systems can require more labour and materials.

Additional Components

Finally, one must consider additional components. System upgrades like a new thermostat or the integration of smart controls, as well as mandatory system cleanings or the adaptation of existing radiators, will contribute to the total boiler installation cost.

Extras such as magnetic filters, which protect the system from sludge build-up, could also be a wise investment that adds to the upfront cost but could save money in the long term on maintenance and energy bills.

The Boiler Replacement Process

Boiler replacement in London involves several crucial steps to ensure that homes are equipped with efficient and reliable heating systems. Starting with a thorough assessment, the journey continues with selecting an appropriate boiler, removing the old unit, and culminating with the precision-led installation of the new appliance.

Initial Assessment

A meticulous appraisal by a certified engineer is the first port of call. This assessment will ascertain the current boiler's condition and heating needs. The engineer evaluates several components such as the boiler's age, its energy efficiency and the size of the property to determine the necessity for a replacement.

Choosing the Right Boiler

Once the need for a new boiler is identified, homeowners must navigate the boiler market's breadth. Selection criteria include the type (combi, system, or conventional), size, brand, and efficiency ratings. High-end models, such as the Worcester Bosch Greenstar CDI Compact, offer long-term energy savings, albeit with higher upfront costs.

Removing the Old Boiler

The process of removing the existing boiler requires careful handling to minimise disruption and potential damage to the property. Engineers will safely disconnect and dismantle the current heating system, ensuring all guidelines are met and the process is compliant with safety regulations.

Installation of the New Boiler

Installing the new boiler encompasses a complex series of actions. Engineers install the unit, connecting it to existing pipes and radiators, and conduct a series of tests. These tests check for leaks, proper pressure levels, and efficient operation. Successful completion assures that the boiler is safe, reliable, and ready to provide uninterrupted warmth.

London Boiler Installation in-depth Prices Breakdown:

Navigating the costs associated with boiler installation in London requires understanding the various elements that contribute to the final price. The type of boiler, the complexity of the installation, and the qualifications of the technician all play significant roles.

Labour Costs

The cost of labour for installing a boiler in London can vary significantly. On average, qualified engineers may charge between £500 and £1,000. Factors influencing this include the engineer's experience, the length of the installation process, and whether any complications arise during the job.

London Combi Boiler Installation Average Costs

For those opting for a combi boiler, the average cost in London tends to hover around £1,800 to £3,000. This figure typically includes a mid-range boiler which merges central heating and hot water production without the need for a separate tank.

System Boiler Cost

A system boiler, which does require a cylinder for storing hot water but not a tank, usually costs slightly more than a combi. Expect to set aside anywhere from £1,900 to £3,500 depending on the boiler brand and capacity.

Conventional Boiler Cost

Opting for a conventional boiler will mean accommodating a cold-water tank as well as a hot-water cylinder and typically leads to a higher price range, with costs often found between £2,200 and £3,800.

Back Boiler to Combi Conversion Cost

Converting from a less efficient back boiler to a combi boiler is a common project in London homes, entailing additional costs for removing the old system and modifying pipework. Costs for such conversions start at around £3,000.

Extras and Additional Equipment

Extra components such as a new thermostat, additional pipework, or upgrading radiators can add to the base cost. These expenses can range from £100 to several hundred pounds depending on choices and necessities.

Potential Grants and Discounts

Some London residents may be eligible for governmental grants or schemes to subsidize their boiler installation. Known initiatives, like the Energy Company Obligation (ECO) scheme, can provide assistance for low-income households to replace outdated and inefficient boilers.

Enhancing Energy Efficiency

Investing in an energy-efficient boiler is not only environmentally responsible but also an effective way to reduce energy bills. Understanding energy efficiency ratings and long-term savings can guide homeowners through making an informed choice.

Choosing an Energy-Efficient Boiler

When selecting a boiler, it's essential to compare the various types available. Condensing boilers are currently the most energy-efficient option in the market, often achieving an efficiency of above 90%. They work by capturing heat that would otherwise escape through the flue and reusing it, which significantly reduces the amount of fuel required to heat a home.

Boiler Efficiency Ratings

Boilers in the UK carry an Energy Efficiency Rating, ranging from G to A+++, with A-rated boilers being over 90% efficient. Sedbuk (Seasonal Efficiency of Domestic Boilers in the UK) is a system used to classify and compare the energy efficiency of boilers. A 90% efficiency rating means that for every pound spent on energy, only 10p is lost, with the remaining 90p effectively used for heating.

Long-Term Energy Savings

Over time, the initial investment in an efficient boiler translates into tangible energy savings. For example, by upgrading from a 75% efficient boiler to one that operates at 85% efficiency, a homeowner can achieve an annual fuel saving of 10% on their energy bills. This can be calculated by deducting the existing boiler efficiency from the new boiler efficiency and then applying this percentage to the annual fuel bill.

<(), the upgrade to a more energy-efficient boiler can not only contribute to a smaller carbon footprint but also to a reduction in monthly outgoings, making the investment financially beneficial in the longer term.

Selecting a Boiler Installation Service

Choosing a reputable boiler installation service in London requires attention to several critical factors, including verifying credentials, comparing different offerings, and understanding the aftercare provided.

Certifications and Approvals

Gas Safe Registered Engineers: It is essential that the engineer installing your boiler is Gas Safe registered, this is a legal requirement in the UK. Verify the registration by requesting their Gas Safe ID card and checking their details on the Gas Safe Register online.

Which? Approved Boiler Installers: Installers with endorsement from consumer organisations like Which? have been rigorously assessed and are typically trusted for their commitment to service quality and customer satisfaction. Seek out these approved professionals to ensure reliability.

Comparing Quotes and Services

When assessing different providers, it is prudent to solicit and compare multiple quotes. Ensure these quotes are detailed, breaking down the costs for the boiler unit, installation, and any additional services.

  • Initial Visitation: Confirm whether companies offer a free initial visit to survey your property and discuss your needs.

  • Itemised Quotes: Look for itemised quotes that display the cost of the boiler, installation, and any additional charges, to enable comprehensive cost comparison.

  • Company Reputation: Research each company's reviews and customer feedback to gauge their reputation in the market.

Understanding Warranty and Support

Boiler Warranty Period: The warranty length on boilers can vary; it's prudent to look for a boiler that comes with a guarantee of several years to protect your investment.

  • Extended Warranty Options: Some installers may offer the option to purchase an extended warranty, providing additional peace of mind.

  • Aftercare Services: Consider the level of aftercare service offered by the installation company. This includes annual servicing, emergency repairs, and support in case of issues with the boiler.

Selecting a boiler installation service requires careful consideration. It's crucial to choose a service that not only meets your needs but also protects you with solid warranties and reliable support.

Safety and Regulatory Compliance

When undertaking a boiler installation in London, adherence to stringent safety protocols and regulatory compliance is paramount. Proper handling of the gas supply and ensuring adequate ventilation are critical to avoid hazardous situations.

Gas Safe Installation Requirements

The primary legal requirement for boiler installations is that they must be conducted by a Gas Safe registered engineer. This ensures that:

  • Safety checks are performed on the gas supply to prevent leaks.

  • Ventilation is adequate, a prerequisite for safe operation.

  • Installation standards meet the Gas Safety (Installation and Use) Regulations 1998.

A valid Gas Safe ID card is essential, depicting the engineer's qualifications regarding the type of gas work they are allowed to perform.

Building Regulations and Standards

Boiler installations in London must comply with the UK Building Regulations, specifically:

A compliance certificate should be issued upon completion, confirming the installation meets the Building Regulations. Regular maintenance and safety inspections are advised to ensure the boiler continues to comply with these standards, guaranteeing not just its efficiency but also the safety of occupants.

Post-Installation Considerations

Once a new boiler is installed, homeowners must consider proper care and the manufacturer's support to ensure its longevity and optimal performance.

Maintenance and Repairs

Regular maintenance of a boiler is essential to its efficiency and safety. Homeowners should schedule an annual service check to catch potential issues early. Common maintenance tasks include:

  • Checking for leaks or corrosion

  • Ensuring the pressure levels are correct

  • Inspecting the flue pathway

  • Cleaning essential components

Regarding repairs, the frequency can vary based on the model age and usage. However, newer boilers may require less frequent repairs compared to older ones.

Boiler Warranty and Aftercare

A boiler's warranty often covers manufacturing defects for a specified period, typically ranging from 1 to 10 years. Homeowners must adhere to the warranty's terms and conditions, which usually stipulate that:

These measures not only keep the boiler in good working order but also validate the warranty, ensuring that any necessary repairs are covered by the manufacturer. It is prudent for homeowners to familiarise themselves with the aftercare services offered by their installer or manufacturer for ongoing support.

Boiler Installation Average Costs per UK Region vs National Average

When assessing the landscape of boiler installation costs across the UK, the prices vary notably by region. London often leads with a higher price range, reflecting the capital's elevated living and service costs.

London: Installation costs can peak due to the demand for space-saving and energy-efficient models.

South East: Costs here follow closely behind London, with a comparative need for efficiency in densely populated areas.

  • Average Cost: Around £2,500 - £3,000 for high-end system boilers including installation.

Midlands: Often presents a moderate cost level, balancing between the south's highs and the north's lows.

  • Average Cost: £1,600+ for basic system upgrades, reaching up to £2,500 for newer models.

North of England: Traditionally offers more competitive pricing, fostering affordability.

Wales & Scotland: These regions can experience variable costs but often align closer with the national average.

These figures place the national average for a new gas boiler at roughly £2,700. However, it's essential to note that specific needs, boiler types, warranties, and regional economic factors can influence the final cost. With price matching and seasonal offers, homeowners are encouraged to seek quotes from multiple providers to secure optimal pricing aligned with their individual requirements.

Environmental Impact of Boiler Installation

When selecting a boiler for installation in London, homeowners must consider not only cost and efficiency but also the device's carbon footprint and broader environmental impact. These assessments ensure a more sustainable approach to heating homes.

Reducing Carbon Footprint

The primary goal of a modern boiler installation is to minimise the environmental impact. Gas boilers and oil boilers differ significantly in terms of emissions. Conventional boilers, typically less efficient, contribute to higher carbon output. Therefore, selecting a unit with a high energy efficiency rating is paramount in reducing one’s carbon footprint. For example, installing a condensing boiler can improve energy efficiency, thereby lowering energy bills and the household's overall environmental impact.

Boiler Fuel and Environmental Considerations

The type of fuel a boiler utilises has direct implications for its environmental friendliness. While gas boilers are common, they produce greenhouse gases. Oil boilers generate more emissions than gas counterparts, thus affecting the location’s air quality. Alternative fuels that are lower in carbon are becoming more appealing, as they offer a viable path to decrease negative environmental impacts. The right fuel type aligns with both energy efficiency and a commitment to environmental wellbeing.

Environmental Policies and Assessments

London’s stringent environmental regulations necessitate thorough assessments before and after boiler installation to ensure compliance. These assessments evaluate the boiler's impact on the local environment, factoring in both its carbon footprint and how it conforms to energy efficiency mandates. Such policies aim to steer the market towards more eco-friendly options, influencing manufacturers and homeowners alike to consider the environmental weight of their choices.


Investing in a reliable boiler installation in London not only escalates the comfort of one's home but also contributes significantly to safety and energy savings. Selecting a boiler with a sterling reputation for quality underpins the long-term performance and satisfaction expected from such a pivotal component of home heating systems.

Notably, brand reputation mustn't be overlooked, as reputable manufacturers provide boilers that exhibit superior efficacy and durability. High-quality boilers ensure optimal operation, thus infusing a sense of assurance in homeowners about their choice. To maximise this aspect, households are advised to consider boilers attached with extensive warranty lengths, which reflect the manufacturer’s confidence in their products.

The merits of professional installation are multifold. It stands as a safeguard against potential gas leaks and carbon monoxide issues, which can be life-threatening. Moreover, an adeptly installed boiler operates at peak efficiency, leading to conspicuous energy savings reflected in reduced utility outlays.

Ultimately, one should discern that the upfront costs, while significant, are mitigated over time by the aforementioned factors. The blend of enhanced safety, augmented energy efficiency, and the peace of mind that ensues from professional installation justifies the initial investment. Homeowners are poised to benefit from a harmonious balance of comfort, safety, and performance, culminating in a wise allocation of resources towards their household heating infrastructure.

iHeat Boiler Installation London

iHeat quotes are completely free, fixed-price, and fully carried out online. The reason we opt for this streamlined process of online quotes is to remove the need for potentially time consuming and progress delaying on-site location assessments when trying to get a new boiler.

iHeat’s quotes are fixed-price to assure customers we are completely transparent in our practices and want to keep them as fully informed as possible during their boiler installation process.

The time frame for iHeat boiler installation usually depends on several factors specific to each unique case, such as:

  • Property type

  • Property location

  • Boiler type (combi, system or heat-only)

  • Conversion or installation

Where possible, iHeat can have your brand new boiler installed and up and running as fast as the next day.

We understand that a boiler is a necessity in any household, therefore aim to complete your installation as fast as possible for you, while still maintaining safety.

iHeat has already revolutionised the heating industry, transforming it from a laborious task that could potentially take weeks into as simple as click, pick and relax.

iHeat New Boiler Costs

Boilers can be a daunting purchase for many people as they’re an appliance with a lot of responsibility, providing heat for you and your family is something you want to get right. Boilers aren’t exactly a quickly disposable item either, potentially lasting you a decade.

Effectively, new boiler cost can be split into two segments: the first is the actual boiler itself (unit price), and the second is the cost of the boiler being installed (set up) in your property by an expert engineer. 

Here at iHeat, we want to remove all of this undue stress and make the decision making process of upgrading to a new central heating system, as easy as possible.

Boiler costs can vary depending on a number of factors including their brand, model, fuel, output, warranty, labour and installation type. Typically a new boiler will cost between £1,845 and £3,500, below is a list of average boiler installations offered by iHeat (guide only).

Installation Type

Price (inc VAT)

Combi to combi swap


Get a quote

System to combi conversion


Get a quote

New boiler install


Get a quote

Back boiler to a combi


Get a quote

System to system


Get a quote

Frequently Asked Questions

How much does it cost to install a boiler in London?

The cost for boiler installation in London typically ranges from £2,000 to £5,000. Precise quotes depend on the boiler model, complexity of the installation, and specific requirements of the property.

Can you provide an estimate for the labour cost of fitting a boiler without parts?

Labour costs for boiler installation in the UK can vary significantly. However, average labour charges excluding parts can be estimated between £500 and £1,000.

What is the price range for a new combination boiler including installation for a three-bedroom house?

For a three-bedroom house in London, the total cost for a new combination boiler including installation can fall between £2,875 and £4,000, factoring in the model chosen and installation complexities.

What are the expected costs for installing a combi boiler and seven radiators in a residential property?

The cost of installing a combi boiler along with seven radiators is contingent on various factors. The prices may range from £3,000 to £5,000, inclusive of both the boiler and the radiators.

How much time is typically required to complete a boiler installation in the UK?

The time required for installing a boiler in a UK home can take anywhere from a few hours to a couple of days. This duration is influenced by the complexity and requirements of the job.

Stephen Day profile photo
Article by
Stephen Day | Co-founder
Gas Safe registered and FGAS certified engineer with over 20 years experience in the heating and cooling industry.