As the UK continues its push toward sustainable energy solutions, more homeowners in London are considering the switch to renewable heating technologies. One of the most popular options is the air source heat pump (ASHP) — a system that extracts heat from the outside air to provide heating and hot water for your home. While it’s an environmentally friendly choice, many people hesitate due to concerns about the initial installation cost. So, how much does it really cost to install an air source heat pump in London?

Let’s break it down.

What is an Air Source Heat Pump?

An air source heat pump works by absorbing heat from the outside air (even in cold temperatures) and converting it into usable heat for indoor spaces and hot water. It operates using electricity but is significantly more efficient than traditional electric heaters, making it a low-carbon heating option.

There are two main types:

1. Air-to-air heat pumps, which heat your home via air blown through fans.

2. Air-to-water heat pumps, which heat water that circulates through radiators or underfloor heating.

In most UK homes, the air-to-water system is more common as it integrates with existing wet central heating systems.

Average Installation Cost in London

The cost of installing an air source heat pump in London varies depending on several factors including property size, heat pump capacity, insulation level, and whether it's a new build or retrofit.

Here’s a general price guide:

1. Basic installation cost: £7,000 – £11,000

2. Larger or more complex installations: £11,000 – £15,000+

3. Luxury or large properties (5+ bedrooms): £15,000 – £20,000+

This estimate includes the heat pump unit, labor, fittings, commissioning, and VAT. However, additional costs may apply depending on the specifics of your property.

Factors That Affect the Cost

1. Property Size and Layout

Larger homes need more powerful units or even multiple heat pumps. More rooms mean more radiators or underfloor heating zones, increasing labour and parts costs.

2. Insulation Levels

Good insulation is essential for heat pump efficiency. If your property is poorly insulated, you may need to invest in upgrading insulation or double glazing. This can add £1,000 to £5,000 to the overall budget.

3. Existing Heating System

If you are replacing an old gas or oil boiler, some plumbing modifications might be needed. You may also need to upgrade radiators or install a new hot water cylinder compatible with the heat pump.

4. Installation Complexity

Installing a heat pump in a well-designed new build is much easier (and cheaper) than retrofitting one into an older home with limited space or awkward layouts. In some London homes — especially older terraced or semi-detached properties — external units may require creative placement or permissions, adding to the cost.

5. Location and Labour Costs

London generally has higher labour costs compared to other parts of the UK. Professional installers may charge anywhere from £300 to £600 per day for labour. Additionally, depending on property access, lifting equipment or scaffolding might be required.

Running Costs and Savings

While the upfront cost can seem high, air source heat pumps are economical in the long run. They typically operate at a coefficient of performance (COP) between 3 and 4 — meaning for every 1kW of electricity used, they produce 3 to 4kW of heat.

1. Average annual running cost: £500 – £1,000

2. Annual savings (compared to oil or electric heating): £300 – £800

Of course, these savings depend on your electricity tariff, insulation, and how efficiently the system is used.

Government Incentives and Grants

To help homeowners make the switch, the UK government offers financial incentives through the Boiler Upgrade Scheme (BUS). As of 2025, eligible households in England and Wales can receive:

1. £7,500 grant towards the cost of an air source heat pump

This significantly reduces the upfront burden. So, if your installation costs £12,000, you could pay just £4,500 after the grant.

You’ll need an eligible EPC (Energy Performance Certificate) and an approved installer to qualify. While London properties often meet the criteria, retrofits may require minor insulation upgrades first.

Is It Worth It?

Switching to an air source heat pump is a long-term investment in sustainability, energy efficiency, and reduced carbon emissions. In London, where housing stock is varied and energy prices are high, a heat pump can deliver tangible benefits — both financial and environmental — over time.

Let’s recap the pros:

1. Lower carbon footprint

2. Lower running costs

3. Government funding available

4. Minimal maintenance

5. Long lifespan (up to 20 years)

And the cons:

1. High upfront installation cost

2. May require insulation or radiator upgrades

3. External unit can take up space and may be noisy

If your home is well insulated and you plan to stay long-term, the initial investment can pay off in both comfort and lower bills.

Final Thoughts

So, how much does it cost to install an air source Room in Roof Insulation London ? Expect to spend between £7,000 and £15,000, depending on your property and needs. However, with the £7,500 government grant, many households will find it more affordable than they first assumed.

Before committing, get multiple quotes air source heat pump in London from qualified installers, and have an energy assessment done. A tailored approach will give you the best idea of total costs and expected savings.

In the long run, an air source heat pump isn’t just a heating system — it’s a step toward a greener, more energy-efficient home.