More than 1.5 million rental properties in England and Wales still fall below EPC band C. The government has not moved the 2030 compliance date for new tenancies, meaning landlords face a collective retrofit bill running into billions. Nationwide’s buy-to-let arm, The Mortgage Works, has now stepped in with a package designed to make that spending less painful, but the real test is whether it moves the needle on a deadline many owners are still ignoring.
As reported by Nationwide, the offer includes a green mortgage product with a reduced rate for properties at EPC A or B, cashback of up to £2,500 for energy-efficiency improvements, and a free advice line connecting landlords to approved retrofit assessors. It is the first major lender-led initiative specifically targeting the 2030 deadline.
Who qualifies, and who doesn’t
The green mortgage rate is available only to landlords whose properties already meet EPC A or B, a tiny fraction of the buy-to-let stock. For the vast majority stuck at D or E, the cashback offer is the practical route in. Landlords can claim up to £2,500 after completing eligible improvements: loft insulation, cavity wall insulation, double or triple glazing, heat pumps, solar panels, and upgraded heating controls. The cashback is paid per property, with a maximum of five claims per borrower.
The catch is that £2,500 will not cover a whole retrofit. A typical 3-bed semi needing cavity wall insulation, loft top-up, and a new boiler runs to roughly £8,000–£12,000, according to Energy Saving Trust figures. Add a heat pump and you are looking at £15,000–£20,000 before grants. The cashback helps, but it is a contribution, not a solution.
What it costs a typical landlord
Consider a landlord with a 3-bed semi in the Midlands, currently rated EPC D. To reach C they will likely need: loft insulation (£500–£800), cavity wall insulation (£1,000–£2,000), double glazing where missing (£4,000–£7,000 for three windows and a door), and a new gas boiler (£2,500–£4,000). Total: roughly £8,000–£13,800. The Mortgage Works cashback knocks off £2,500, leaving £5,500–£11,300 out of pocket per property.
That is before any rent increase to recover the cost. Under current rules, landlords cannot raise rent above the market rate simply because they have improved the EPC. The payback period depends entirely on the property’s energy savings: a shift from D to C typically cuts gas use by 15–25%, saving a tenant around £200–£350 a year. For the landlord, the return comes only when they sell or refinance.
Grants and schemes to stack alongside
The Mortgage Works package does not exist in isolation. Landlords should layer it with existing government support. The Boiler Upgrade Scheme offers £7,500 off an air-source heat pump, enough to cover most of the installation cost. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The ECO4 programme targets low-income areas but can also cover solid wall insulation in some cases.
But the stacking requires timing. Most grants have application windows, income thresholds, or property eligibility rules. Landlords with tenants on benefits or in lower council tax bands may qualify for deeper subsidies. Those with higher-value properties in prime rental areas often find themselves excluded from the free schemes and reliant purely on lender cashback and their own capital.
What this means for the wider rental market
The Mortgage Works move is a signal, not a silver bullet. Other lenders are watching. If Nationwide’s package reduces defaults or improves portfolio performance, expect Barclays, Lloyds, and Santander to follow with similar offers. The government has not yet announced enforcement penalties for missing the 2030 deadline, but the direction of travel is clear: properties below EPC C will become increasingly hard to mortgage, insure, and let.
Landlords with a handful of properties can act now. Those with larger portfolios need a phased plan, prioritising the worst-rated homes first, stacking grants and cashback, and budgeting for the remainder. The 2030 deadline is 2,100 days away. At one retrofit per quarter, a landlord with 20 properties can just about clear the backlog in time.
Frequently Asked Questions
Yes. The cashback is paid by the lender for eligible improvements, while the Boiler Upgrade Scheme is a government grant. They are separate pots and can be used together on the same property, provided the work meets both schemes' criteria. Always check with your installer and lender before starting.
The government has not yet confirmed penalties, but letting a property below EPC C for a new tenancy after 2030 will likely be illegal. Existing tenancies may be exempt until they end. Lenders may also refuse mortgages or demand higher rates for non-compliant properties. Best to start upgrades now.
