Ireland has millions of pre-1980 homes, many with solid stone or brick walls, single-glazed windows, and oil or solid fuel boilers. Can these homes benefit from a heat pump?
The honest answer: yes, but it takes more work and planning than a newer home. The SEAI grant system recognises this by including substantial grants for both insulation and heat pumps that are designed to be combined.
The key challenge: heat loss
A heat pump works best when the heating system operates at low flow temperatures (35–45°C). This is efficient and gives high SPF values. But a poorly insulated older home loses heat quickly and needs either a larger heat pump running continuously, or higher flow temperatures, both of which reduce efficiency.
The solution is to reduce heat loss first. SEAI recommends achieving a BER of B3 or better before installing a heat pump.
Typical works for an older home
| Priority | Work | Approximate cost (before grants) |
|---|---|---|
| 1st | Attic insulation (if accessible) | €1,000–2,000 |
| 2nd | Wall insulation (cavity or external) | €5,000–25,000 |
| 3rd | Air-to-water heat pump + controls | €9,000–18,000 |
| 4th | Radiator upgrades if needed | €1,500–5,000 |
For a solid-wall detached house needing external wall insulation plus a heat pump, total costs before grants can reach €30,000–40,000. However, SEAI grants can cover €20,500+:
- External wall insulation: up to €8,000
- Heat pump (unit + heating + bonus): up to €12,500
The BER assessment route
Before starting work, get a BER assessment (grant available: €50 for individual scheme, €350 for home energy assessment via OSS). The BER assessor will tell you:
- Current energy performance and heat loss
- What upgrades are recommended
- Estimated BER after upgrades
This gives you a road map and helps prioritise the best-value upgrades.
Radiators in older homes
Many older Irish homes have large cast iron radiators or long lengths of steel radiators. These are often an advantage for heat pumps, as their large surface area delivers adequate heat even at the lower flow temperatures heat pumps prefer.
If your home has smaller modern steel panel radiators sized for a boiler (typically 60–70°C flow), these may need upgrading. This cost is included in the €2,000 central heating upgrade grant.
Case study: 1960s semi-detached in Dublin
A typical 1963 semi-detached in Dublin with:
- Cavity walls insulated (after grant: ~€500 net)
- Attic insulated (after grant: ~€200 net)
- Air-to-water heat pump installed (after €12,500 grant: ~€1,000–3,500 net)
Estimated annual savings vs previous oil boiler: €1,500–2,000/year based on 2026 energy prices.
Warmer Homes Scheme for low-income households
If your household receives Fuel Allowance or other qualifying payments and your home is rated E, F, or G, the Warmer Homes Scheme can fund all works at no cost to you.