Heat pump in a flat: what changes
In a flat, the area is small, the outdoor unit goes on a shared façade and the CEE bonus follows its own scale. The calculator starts from 60 m².
An individual heat pump in a flat is possible, but the outdoor unit goes on a balcony, terrace or façade, often common parts or changing the building’s outward look: the co-owners’ general meeting usually has to approve it, and the building rules and the neighbours’ peace must be respected. The choice depends on the existing heating. With individual gas central heating, an air-to-water heat pump can take over the water radiators; it qualifies for MaPrimeRénov’ (up to €5,000) and for the CEE bonus of sheet BAR-TH-171 for flats: 48,700 kWh cumac base, halved under 35 m² and cut by 30% from 35 to 59 m². With electric heaters, the usual answer is an air-to-air heat pump, simpler to fit, with no MaPrimeRénov’ in 2026. Individual ground-source heating is out of reach in a flat. The calculator costs air-to-water and air-to-air running costs; the air-to-air CEE bonus (sheet BAR-TH-129) is not calculated here.
Estimated out-of-pocket cost
€10,211
€15,788 − €5,577 in grants
| Estimated price (median quote) | €15,788 |
| MaPrimeRénov’ (purple) | €3,000 |
| CEE bonus (Coup de pouce) | €2,577 |
| Out of pocket | €10,211 |
| Heating per year today | €1,276 |
| Heating per year with heat pump | €558 |
| Saving per year | €719 |
| Payback | 14.2 years |
| Heating need | 8,150 kWh |
| Climate (St-Genis-Laval) | 2,058 DJU, H1 |
Outside Île-de-France ceilings for 3 people: blue ≤ €30,540, yellow ≤ €39,148, purple ≤ €55,196. Estimate only: the Anah alone sets the grant, and the CEE amount is the one the firm puts in writing before you sign.
Checked by Radif Partners · Editorial policy · Method and sources
The CEE bonus in a flat
For an air-to-water heat pump replacing a gas boiler, here is the volume under sheet BAR-TH-171 for flats with Coup de pouce, and its value at the registry average price:
| Heated area | Zone H1 | Zone H2 | Zone H3 |
|---|---|---|---|
| under 35 m² | 146,100 (€1,289) | 121,750 (€1,074) | 85,225 (€752) |
| 35 to 59 m² | 204,540 (€1,804) | 170,450 (€1,503) | 119,315 (€1,052) |
| 60 m² and over | 292,200 (€2,577) | 243,500 (€2,148) | 170,450 (€1,503) |
A blue or yellow household sells its certificates at the higher “fuel poverty” price (€14.64 per MWh cumac against €8.82). These are market values: each supplier sets its own price.
Air-to-water or air-to-air?
Air-to-water replaces a boiler and keeps the water radiators and often hot water; it gets MaPrimeRénov’ and the CEE bonus, but costs more (median €15,788 across published quotes, mostly houses). Air-to-air blows warm air through wall units, replaces electric heaters and cools in summer; it costs less (median €7,618), without MaPrimeRénov’. In an electrically heated flat, air-to-air is the usual case: see replacing electric heaters.
Lower heating needs
A flat loses less heat than a house of the same area: it has neighbours above, below and to the sides. The calculator cannot know this; choose “good” insulation if you are on a middle floor, or enter your real consumption under “Refine”. The output needed is often 3 to 5 kW, which keeps the price down, but also the yearly saving and so the financial case for air-to-water.
Shared heating
If the building has a shared boiler room, switching energy is decided at the general meeting for the whole building, with other grants (MaPrimeRénov’ Copropriété, collective CEE sheets). This site only costs individual installations.