THE DERBY FIELD GUIDE / AIR SOURCE HEAT PUMPS
Give competing installers the same heat-loss report. In Derby, the differences in radiator changes and flow temperature then become visible.
START WITH THE PROPERTY
For a Derby project, collect the same heat-loss report, radiator list and existing heating photographs for each installer. That makes differences in assumptions visible instead of burying them inside totals.
BEFORE YOU ACCEPT A QUOTE
If one quote specifies more emitter upgrades or a different flow temperature, ask why. The useful comparison is whether each design heats the same rooms under the same survey conditions.
LOCAL COST EVIDENCE / OCTOBER 2026
A quoted installation price depends on the work inside the home. Electricity use depends on the finished design and tariff.
We could not verify a representative local average for a fully installed, family-sized system. Published installer figures mix starting prices, example homes and different scopes. Averaging them would suggest more certainty than the evidence allows.
For a useful comparison, ask each installer to itemise the heat pump, cylinder, radiator changes, electrical work and commissioning, then show the price before and after any eligible grant.
about £770approximate annual cost if the October–December 2026 unit rate lasted a full year
This is a model, not a measured bill or an average for families with heat pumps. It starts with 11,090 kWh, the 2024 mean annual domestic gas use per meter in Derby. We apply 85% boiler efficiency and a heat pump seasonal performance factor of 3.1, then price the electricity at 25.36p per kWh in East Midlands.
Calculation: 2024 mean gas kWh per domestic meter × 0.85 ÷ 3.1 × Ofgem electricity unit rate. The result is rounded to the nearest £10. It assumes the gas meter's entire use was for heating and hot water, so cooking and other gas use can make it too high. It does not include existing electricity standing charges, servicing, or changes to your other electricity use.
Gas consumption is by local authority, except London, which uses the London region. Oxfordshire combines its five districts by gas-meter count. The electricity rate follows the distribution region for the place; Oxfordshire spans two regions. Actual cost depends on your heat-loss survey, hot-water use, chosen tariff, controls and the installed system's measured performance. Ask the installer for a property-specific annual estimate.
ILLUSTRATIVE QUOTE COMPARISON
One installer proposes several emitter changes at a lower flow temperature.
Another retains existing radiators and gives no room-level outputs.
Share one heat-loss report with both and ask for a room-by-room explanation. The disagreement can reveal a missing calculation or a deliberate performance tradeoff.
ANOTHER PROJECT AT THE SAME ADDRESS?
NEXT STEP IN DERBY
When room designs are comparable, check cylinder sizing, control strategy and commissioning. These can explain a price difference that is not visible in the heat-loss figures.