Does a 1960s flat qualify for the Boiler Upgrade Scheme?

Yes — the £7,500 BUS grant applies to any owner-occupied or privately rented property in England or Wales with a valid EPC. Leasehold + freeholder consent required — typically the BIGGEST blocker for flat heat pump installs.

What size heat pump do I need for a 1960s flat?

3–6 kW thermal output is typical, with 5 kW being the median. The exact size depends on a heat-loss calculation per BS EN 12831, which your MCS-certified installer performs on a site visit.

What pre-install work is typically needed?

Freeholder permission in writing (can take 4–12 weeks). Loft insulation to 270 mm (for top-floor flats only). An MCS-certified installer will confirm the exact scope on a site visit and price it into the quote.

Heat pump for a 1960s flat: 2026 cost + sizing guide

What makes a 1960s flat different

Post-war system-built flat (council or private), single-aspect, typical 45–75 m² floorplate.

From a heat-pump-sizing perspective, a 1960s flat has a design heat loss of 50–85 W/m² at the UK standard −2°C external design temperature (per PAS 2035). That translates to an annual space-heat demand of around 5,000–10,000 kWh and a recommended air-source heat pump capacity of 3–6 kW thermal. Smaller than gas-boiler sizing typically lands at — heat pumps run 24/7 at lower flow temperatures rather than cycling at 70°C.

Heat pump sizing + install figures — 1960s flat
Parameter	Typical range	Notes
Floor area	45–75 m²	BEIS English Housing Survey median.
Design heat loss	50–85 W/m²	At −2°C external (UK design temp).
Annual heat demand	5,000–10,000 kWh	Space heating only, not DHW.
Recommended ASHP size	3–6 kW	Per BS EN 12831 sizing.
Pre-grant install cost	£8700–£13100	Including pump, cylinder, 1–3 radiator upgrades.
After BUS grant	£1200–£5600	£7,500 deducted by installer at invoice.
Common EPC band	Band D	Before retrofit work.
Typical install time	2–3 days	Whole-house including cylinder + radiator swaps.

Heat pump sizing + install figures — 1960s flat— Ranges are typical for the archetype; specific quote depends on property survey by an MCS-certified installer.

BUS grant eligibility specifics for this property type

Leasehold + freeholder consent required — typically the BIGGEST blocker for flat heat pump installs.
Communal heating systems are NOT BUS-grant eligible at the individual-flat level; whole-building scheme needed via the freeholder/landlord.
Outdoor unit placement on balcony / external wall must clear MCS 020 noise rules + leasehold restrictions on external alterations.

Pre-install upgrades typically needed

Most 1960s flats need some fabric or radiator work before the heat pump can be commissioned. The most common scope:

Freeholder permission in writing (can take 4–12 weeks).
Loft insulation to 270 mm (for top-floor flats only).
Air-to-air monobloc heat pump may suit better than wet system in some flat layouts (no cylinder needed).
If currently storage heaters: replumb to wet system is a major project — air-to-air units often more practical.

The full scope is set by your MCS-certified installer’s heat-loss calculation. Most installers absorb the radiator swap and cylinder install within the BUS-grant pricing — you don’t have to coordinate them separately.

Is this archetype right for you?

Top-floor flat owners with freeholder consent + south or east-facing balcony for outdoor unit. Hardest archetype to get to BUS-grant install but the install scope itself is small.

Check your specific home

The figures above are typical for the archetype. Your specific property may sit at either end of the range depending on orientation, occupancy and prior retrofit work. Run a free Propertoasty pre-survey — combines your address, EPC and Google Solar API roof data into an installer-ready report in about five minutes.