The first 15 of these units were released for letting in September 2024 with the next phase being available in December 2024.
Now, not only do these innovative heating systems help tenants cut down on energy bills, but they also provide landlords with an opportunity to increase property value. As sustainability becomes a key driver in modern developments, ASHP heat pumps are proving to be a win-win solution—delivering both eco-friendly benefits and long-term savings to property owners.
This article will look at what an air source heat pump is, its advantages, and discuss the innovative Marylebone Quarter project. With these insights, you’ll see how modern heating solutions are paving the way for more sustainable, cost-efficient living.
What is an Air Source Heat Pump(AHSP)?
An air source heat pump, also known as an air-to-water heat pump, extracts heat from the outside air and transfers it to water. This heated water is then used to warm rooms in your home through radiators or underfloor heating systems. Additionally, it can heat water stored in a hot water cylinder, providing hot water for taps, showers, and baths.
How Does an Air Source Heat Pump Work?
An air source heat pump absorbs heat from the outdoor air into a fluid. This fluid is then circulated through a heat exchanger within the heat pump, where its temperature is increased. The heat is then transferred to water, which can be used for heating purposes or stored for domestic hot water needs.
What is the Cost of an Air Source Heat Pump?
The cost of an air source heat pump can vary depending on the properties you wish to heat, the model of an air source heat pump, and the complexity of the installation. However, the long-term benefits far outweigh the initial costs of heat pumps and installation. Landlords can expect to invest between £7,000 and £11,000 for a typical air source heat pump system.

What are the Benefits of Air Source Heat Pumps For Residents and Landlords?
The combination of energy efficiency, sustainability, and low-maintenance requirements of ASHP offers a range of benefits that make installing one a smart decision.
Energy Efficiency
ASHPs provide more energy than they consume, resulting in lower energy bills for residents. Additionally, while the initial installation costs for ASHPs might be higher than traditional systems, the long-term savings on energy bills and maintenance costs make them a financially sound investment for landlords. Over time, the reduced operational costs and potential for increased rental income can offset the upfront expense.
Sustainability
Using renewable energy from the air, ASHPs contribute significantly to lower carbon footprints compared to traditional gas boilers, which emit CO2 into the atmosphere.
Low Maintenance
ASHPs generally require less maintenance than traditional heating systems, reducing operational costs over time.
Incentives
In the UK, landlords who invest in energy-efficient technologies like ASHPs may qualify for government grants or incentives, which can help offset installation costs and increase the overall return on investment. This could be possible through the Boiler Upgrade Scheme or Home Upgrade Grant.
Specific Reasons for Choosing ASHP Heat Pumps in the Marylebone Quarter
The decision to install ASHPs at Marylebone Quarter was driven by several compelling reasons:
Regulatory Compliance
By upgrading to ASHPs, the EPC (Energy Performance Certificate) rating of the flats improved from D to B, meeting stringent regulatory standards and enhancing the property’s market appeal. While B-rated options might have a higher upfront cost, the long-term savings on energy bills and the positive environmental impact can make them a worthwhile investment.
Increased Property Value
Prospective tenants value the enhanced energy efficiency provided by ASHPs, making the flats more attractive in a competitive rental market. Additionally, properties equipped with ASHPs are often seen as more modern and eco-friendly, making them more attractive to potential tenants. This can help landlords command higher rental prices, increase occupancy rates, and enhance the overall appeal of the property.
Reduced Operating Costs
The removal of antiquated gas boilers and water tanks has significantly reduced maintenance and compliance costs, enhancing overall operational efficiency.

Case Study: Addington Capital and Heitman LLC
Addington Capital and Heitman LCC chose air source heat pump cylinders for their residential development in Marylebone.
Project Overview
The redevelopment of Victorian residential blocks in London’s West End into seventy modern flats.
Implementation Process
ASHP heat pumps were chosen to future-proof the development, replacing gas combination boilers. This strategic move not only improved the EPC and EIR (Environmental Impact Rating) but also aligned with sustainability goals, reducing the carbon footprint of Miles Buildings.
Challenges and Solutions
Overcoming logistical challenges such as finding suitable locations for ASHP units and installing extractor vents were crucial. Collaborating closely with development partners ensures minimal disruption to living spaces while maximising energy efficiency.
Performance Metrics
By Addington Capital and Heitman LCC upgrading to ASHPs, this improved EPC ratings to B standards and transformed the Environmental Impact Rating from E to A, showcasing substantial energy savings and environmental benefits.
Effective Heating Solutions For Flat Rentals
Transitioning from gas boilers to ASHPs at Marylebone Quarter proves to be a forward-thinking choice for rental developments. Not only does it eliminate the compliance burden of annual gas tests but it also reduces servicing requirements and operational costs. Most importantly, this shift underscores a commitment to sustainability, significantly lowering the carbon footprint of Miles Buildings.
For developers aiming to enhance environmental performance and operational efficiency in their projects, ASHPs present a compelling case. The success story of Addington Capital and Heitman LLC at Marylebone Quarter highlights the transformative impact of ASHPs in modern residential developments.
Add Living Are Your Accredited Partners in Property Management
If you’re considering Add Living for your property management needs, we specialise in delivering comprehensive asset and property management services across the UK, focusing on prime locations like London and Leeds. We pride ourselves on offering direct, personalised service with a dedicated property manager assigned to each client. This direct communication ensures efficient and effective management, without the complications of intermediaries.
As accredited property managers, we maintain high standards of customer service, supported by our membership with The Property Ombudsman and TDS Insurance. These credentials provide a foundation of trust and protection for both leaseholders and residents, safeguarding their interests throughout the tenancy.
Choose Add Living for expert property management that prioritises customer satisfaction, operational efficiency, and financial security. Join our satisfied clients who have rated us excellent based on their experiences with our dedicated services.

