We retrofitted an end-of-terrace family home in east Oxford, helping ensure that every room in the home was comfortable, and cutting carbon emissions for the family.

About the home

Jan Rosenow’s home is an end-of-terrace house in East Oxford, dating from the 1880s with solid brick walls. The family moved in 2014, knowing it would be a long-term renovation project.

The renovation included extensions on both the ground and first floors, as well as a loft conversion, resulting in a house with a mix of old and modern parts.

Motivations for the retrofit

Increasing comfort

When the family moved in, it was clear there was much work to be done to make every room comfortable—warm in the winter and cool in the summer. Therefore, improving home comfort was a key reason for undergoing retrofit measures to enhance the property’s energy efficiency and reduce heat loss.

“Reducing carbon emissions was our key driver for undertaking the home retrofit.”

Jan Rosenow, Cosy homes Oxfordshire client

Reducing carbon emissions

Alongside this, reducing carbon emissions was a key priority for the family. Jan works in energy research and advises policymakers on retrofitting homes, so he understands the environmental impact of our homes. It was important to him to practise what he preached, ensuring his own home was compatible with a net-zero carbon emissions future.

What measures were installed?

Jan had already installed an Air Source Heat Pump (ASHP) in his home (not by our team).

Air Source Heat Pumps are a low-carbon heating method that uses warmth from the air to heat the building. They are less intensive than traditional gas boilers and radiators, operating at lower temperatures. For ASHPs to be effective and cost-efficient, the building must be airtight and well-insulated to minimise heat loss. Therefore, Jan’s retrofit focused on achieving these goals.

In the home, they had already installed floor and loft insulation during their loft conversion, so additional retrofit measures in this phase included:

• Installing Internal Wall Insulation (IWI) for the previously uninsulated front of the house, including the bay window space. They chose wood fibre insulation as a natural, sustainable option (see below images).
• Replacing windows with triple glazing where needed, especially the older sash windows.
• Replacing the old front door to reduce draughts.

The impact of the home retrofit

Before the retrofit measures were installed, the family noticed a clear difference between parts of their home.

The new build extensions on the ground and first floors were built to modern performance standards and were definitely warmer and more comfortable compared to the older parts of the house.

After improving the home’s insulation, replacing windows, and draught-proofing the front door, this difference is much less noticeable, with the entire house maintaining a comfortable temperature throughout.

The air source heat pump also provides a more constant source of heat, contributing to the overall comfort.

These improvements have also significantly reduced the family’s heating bills by 60%. This is largely because the home is now well-insulated and retains heat all day long, allowing them to move onto a flexible tariff with their energy provider, which is significantly cheaper. They expect the heat pump will pay for itself through these savings in six years, highlighting the long-term cost benefits.

“If you want a proper retrofit survey and support with project coordination and making the right decisions, Cosy Homes Oxfordshire is the way to go.”

Jan Rosenow, Cosy Homes Oxfordshire client