Nearly 19 million homes in England have an EPC rating of D or below. That is the blunt arithmetic behind a policy that Property118 warns will ‘damage the housing sector’, and one that could hit every homeowner’s wallet within six years.
As reported by Property118, the proposed mandatory minimum EPC C for owner-occupied homes by 2030 risks creating a two-tier market. The government has not yet legislated the owner-occupier target, but the trajectory is clear, and the costs are not.
Who pays for the upgrade gap
Energy Saving Trust estimates that lifting a typical 1930s semi from EPC band D to C costs between £10,000 and £15,000. That covers cavity wall insulation, loft top-up, double glazing, and a new boiler. For a solid-wall Victorian terrace, the bill can reach £25,000. The government’s Boiler Upgrade Scheme offers £7,500 for a heat pump, but only if you scrap your gas boiler first, and it does not cover the fabric upgrades EPC C demands.
Ofgem’s data shows fewer than 60,000 households used the scheme in its first two years. That is roughly 0.2% of the homes that need upgrading. The Great British Insulation Scheme, which targets low-income households, has installed measures in just 400,000 homes since 2023, against a need of 19 million.
Yet the Treasury has confirmed no new grant programme for owner-occupiers. The policy therefore assumes either that households will self-fund, or that the market will somehow absorb the cost. Neither assumption holds for the 8 million households with less than £1,000 in savings, according to the Financial Conduct Authority.
What the EPC metric misses
The deeper problem is that the EPC methodology itself is out of date. The current rating uses the Standard Assessment Procedure (SAP) from 2012, which heavily weights the cost of fuel rather than carbon emissions. A gas boiler scores well because gas is cheap per kWh. A heat pump scores worse because electricity is three times the price per unit, even though it emits half the CO₂.
This creates perverse incentives. A homeowner who installs a heat pump and solar panels might still see their EPC stuck at D if the property has single glazing or solid walls. Meanwhile, a neighbour with a new gas boiler and cavity wall insulation can hit C without touching their roof or windows. The policy therefore rewards fossil fuel lock-in, exactly when the grid is decarbonising.
The government’s own consultation on EPC reform, due in 2025, proposes adding a ‘smart readiness’ indicator and a fabric performance metric. But until those changes arrive, the current system will continue to misdirect the £15 billion the Climate Change Committee says is needed for domestic retrofit by 2035.
What homeowners can do now, without waiting for policy
The catch is that doing nothing is also risky. Mortgage lenders are already offering ‘green mortgages’ with lower rates for EPC A or B homes, and some insurers now ask for EPC ratings before quoting for buildings cover. A D-rated home could face higher premiums or refused cover within five years.
Homeowners can act on three fronts without waiting for the government. First, book an EPC assessment now, not to sell, but to get a baseline. Second, prioritise the measures that give the biggest EPC jump per pound: loft insulation costs £500–£600 and typically adds 5–10 points; cavity wall insulation costs £1,000–£1,500 and adds 10–15 points. Third, install a heat pump only after improving the fabric, otherwise the system will run inefficiently and your EPC will barely move.
Energy Saving Trust’s local advice centres offer free home energy visits. The scheme is underused, fewer than 50,000 households used it in 2023, despite being the cheapest way to get tailored, non-commercial advice.
The alternative is to wait for a policy that may never be fully funded, and hope the market does not punish your home in the meantime. That is a gamble most households cannot afford.
Frequently Asked Questions
Not yet. The 2030 target for owner-occupied homes has not been legislated. The mandatory EPC C requirement currently applies only to new tenancies in the private rented sector from 2028. However, mortgage lenders and insurers are already using EPC ratings to price risk, so upgrading voluntarily may protect your home's value.
Loft insulation (£500–£600) and cavity wall insulation (£1,000–£1,500) typically provide the largest EPC score increase per pound spent. A combination of both can lift a typical D-rated 3-bed semi to a C for under £2,000. Heat pumps and solar panels offer longer-term savings but cost £7,000–£15,000 and may not shift your EPC band if the building fabric is poor.
