Client overview
This case study examines the retrofit of a mid-terrace house in Hull, East Yorkshire, which had a very poor F-rated Energy Performance Certificate. Through the replacement of inefficient electric storage heaters with an air source heat pump, alongside the installation of a rooftop solar PV system, the property achieved a significant improvement to an EPC rating of B — highlighting how outdated electric heating in terraced housing can be replaced with a modern, efficient renewable system to transform a property's energy performance.
The challenge
Mid-terrace properties heated by electric storage heaters are among the least efficient and most expensive homes to run, given the high cost of electricity used for direct resistive heating and the limited ability of storage heaters to respond to a household's actual heating needs. Starting from an F-rated EPC, the property faced high running costs, poor heat retention, and outdated heating infrastructure. The objective was to remove the reliance on old storage heaters and replace them with a more efficient, controllable heating system, while introducing on-site renewable generation to further reduce the property's energy costs.
Project goals
Remove storage heater reliance
Eliminate dependence on old electric storage heaters — among the least efficient and most expensive ways to heat a home.
Improve the EPC rating
Starting from an F-rated EPC, deliver a substantial uplift through modern heating and generation technology.
Add renewable generation
Introduce on-site solar electricity generation to further reduce the property's energy costs.
The solution
Ideal air source heat pump
An Ideal air source heat pump with a pre-plumbed cylinder was installed to replace the existing electric storage heaters, providing efficient space and water heating in place of the old direct electric system.
6-panel solar PV array
A 1.515kW solar PV system was installed as a single 6-panel array to generate renewable electricity on site, helping to offset consumption from the new heat pump and the wider household.
Results & benefits
EPC improvement
The property's EPC rating rose from F to B — a substantial improvement reflecting the scale of the upgrade from outdated electric storage heating to a modern heat pump and solar setup.
Modern, controllable heating
The old electric storage heaters were removed entirely, replaced with an Ideal air source heat pump and pre-plumbed cylinder for a far more efficient and controllable heating system.
Renewable generation
A specific bill savings percentage was not recorded for this installation, but replacing electric storage heaters with an air source heat pump and adding solar generation is expected to deliver a meaningful reduction in the household's running costs.
“This Hull mid-terrace house shows the impact of moving away from old electric storage heating towards a modern air source heat pump paired with solar PV. Lifting the property from an EPC rating of F to B demonstrates how even homes with historically poor and expensive heating systems can achieve a strong efficiency uplift. For homeowners in similar terraced properties still relying on electric storage heaters, this case shows a clear path to a more efficient, lower-carbon home.”
YEERS Project Summary, Mid-Terrace House, Hull
