Pre-1900s mid-terrace in Oxford
Could your home be made warmer, cheaper to run, and better for the planet? See what’s possible when you take a whole-home approach to planning energy upgrades.
What’s the potential of a home like this?
This historic mid-terrace in Osney Island, Oxford, is typical of many older homes in conservation areas. With solid brick and cavity walls, timber windows (a mix of single, secondary, and double glazing), and a pitched roof with rooms in the roof, it faced significant heat loss and high bills.
The homeowners wanted to cut carbon, improve comfort, and reduce draughts while preserving the character of their house. With a Whole House Plan, they could see which upgrades mattered most and how to phase them over time.
Here’s what the plan revealed:
| Carbon emissions could be cut by over 90% |
| The EPC rating could rise from 67 D to 91 A |
| Annual fuel bills could fall from £3,548 to under £800 |
You don’t have to carry out every measure at once. The Whole House Plan gives you a roadmap so you can make improvements in your own time, at your own pace, and within your budget.
“We started with the relatively easy ways to improve insulation in an old house: we put in better doors and double-glazed windows. Then, the biggest change we made was to put in an Air Source Heat Pump as these are said to be more efficient than a gas boiler. That was a big gain.”
Iain, Osney Island
Where this home stands now
House profile
| EPC rating | Current 64 D > Potential 92 A |
| Type | Mid-terrace |
| Built | Pre-1900s |
| Location | Osney Island, Oxford (conservation area) |
| Occupancy | Owner-occupied |
| Bedrooms | 5 |
| Floor area | 177m² |
| Walls | Solid brick and cavity |
| Floors | Solid concrete |
| Roof | Pitched with rooms-in-roof |
| Windows | Timber, single/secondary/double glazed |
| Annual energy use | 25,712 kWh (146 kWh/m²) |
| Carbon emissions | 5.2 tonnes CO2/year |
The EPC rating: now vs potential
An EPC rates your home’s energy efficiency – from A (best) to G (worst). A higher score can mean lower bills, but it doesn’t guarantee comfort. Whole-home upgrades help bridge that gap.
Long-term comfort, short-term disruption
| Key to tables: | Low impact: • | High impact: •••••• |
| Minor measures | Comfort & health | Disruption |
|---|---|---|
| Draught-excluder for chimney flue | ●●●●● | ● |
| Increase loft insulation to 300mm | ●●●● | ●● |
| Insulate sloping ceiling of rear extension | ●●●● | ●●● |
| Internal wall insulation to timber frame wall | ●●●● | ●●●● |
| New insulated front door | ●●●●● | ●● |
| Ventilation improvements | ●●●●●● | ●● |
| Major measures | Comfort & health | Disruption |
|---|---|---|
| Upgrade room-in-roof insulation | ●●●●● | ●●●●● |
| External wall insulation | ●●●●● | ●●● |
| Solid floor insulation | ●●●●● | ●●●●●● |
| New double-glazed timber windows | ●●●●●● | ●●●● |
| Air source heat pump | ●●●●●● | ●●●● |
| Measure | Comfort & health | Disruption |
|---|---|---|
| Solar PV | ● | ●● |
Expert tip
“This house is in a conservation area where measures affecting the external appearance of the house must be approved. The homeowners were allowed to install external wall insulation because their house is rendered at the front and so the appearance wouldn’t change much.”
Geordie Stewart, Scheme Manager
The difference each step could make
These figures show how each recommended measure could affect the home’s EPC rating, energy bills, and carbon emissions – if installed in the order shown. They’re based on a full Whole House Plan tailored to this property.
| Measure | Est. cost | EPC | Fuel bill | CO₂/year |
|---|---|---|---|---|
| Where you are now | – | 64 D | £3,297 | 5.21 t |
| Draught-excluder for chimney | £50–£100 | 65 D | £3,250 | 5.13 t |
| Increase loft insulation | £1.5k–£2k | 68 D | £2,914 | 4.56 t |
| External wall insulation | £12.5k–£17.5k | 70 C | £2,676 | 4.15 t |
| Ventilation improvements | £1.5k–£2.5k | 70 C | £2,676 | 4.15 t |
| Internal wall insulation (front timber wall) | £3k–£5k | 71 C | £2,589 | 4.01 t |
| Sloping ceiling insulation (rear extension) | £3k–£5k | 72 C | £2,562 | 3.96 t |
| Room-in-roof insulation | £7.5k–£15k | 72 C | £2,532 | 3.91 t |
| New timber sash windows | £35k–£55k | 74 C | £2,357 | 3.62 t |
| New insulated door | £2k–£5k | 74 C | £2,336 | 3.59 t |
| Air source heat pump | £13.5k–£17.5k | 81 B | £1,861 | 0.69 t |
| Solar PV (2.5 kWp) | £4k–£6k | 92 A | £665 | 0.25 t |
Boost your EPC rating
Installing a single major system like a heat pump or solar panels can still make a big difference. These examples show how individual upgrades could shift the home’s EPC and reduce carbon emissions – even before doing everything else.
| Upgrade option | EPC rating | Fuel bill | CO₂ emissions |
|---|---|---|---|
| Just solar PV | 81 B | £1,479 | 3.71 t |
| Just heat pump | 79 C | £2,087 | 0.77 t |
| Solar + heat pump | 89 B | £891 | 0.33 t |
Expert tip
“The owners decided to replace some of their single glazed windows with double glazing to reduce heat loss and improve comfort levels in particular rooms. They installed double glazed timber sash windows to meet conservation area requirements and match the period features of the house.”
Natasha Ginks, Retrofit Coordinator
These stories are here to inspire
Every home is unique, and the best way to use them is as a guide to picture what’s possible for yours.
Find more tips on making the most of the case studies here.
Need help or advice with costs? Check out our page on help with the cost of home retrofit for grants, advice, and other resources.
Wondering what’s right for your home?
A Whole House Plan gives you expert, independent advice on the best steps to take – and in what order – so every upgrade really works.
Don’t put it off another year. Take the first step with a free consultation. Our team of experienced Retrofit Advisers will listen to your goals, help you understand what’s possible, and outline the best next steps – no pressure, no obligation.
Smarter home upgrades. Backed by trusted retrofit expertise.
A partnership project
A House Like Mine is an Oxford City Council initiative, delivered as part of the Zero Carbon Oxford Partnership (ZCOP) in collaboration with Cosy Homes Oxfordshire. The idea was first developed through case studies in Charlbury, and has since been expanded to show what’s possible for homes across Oxford and Oxfordshire.
It’s designed to help you take the first step towards making your home cosy, energy-efficient, and ready for the future. Step by step.
A House Like Mine was funded by the MCS Foundation, Oxfordshire County Council, Oxford City Council, and Lucy Group. The case studies are licensed under a Creative Commons BY-NC-ND 4.0 licence (creativecommons.org).
Prefer a PDF version?
Download a shareable PDF of this case study – perfect for your community group, local class, or anyone curious about improving home energy efficiency.
We’re making this resource freely available to raise awareness of how retrofitting – upgrading your home to use less energy and stay comfortable year-round – can make a real difference.
Click here to download the PDF