Energy Performance Certificates used to be a formality. You paid an assessor £60, got a certificate with a letter on it, and nobody looked at it again. That’s changed. Lenders now treat the rating as part of their risk assessment, green mortgage products reward higher bands, and minimum energy standards for rented homes mean an F or G rating can stop a property being let at all. “Unmortgageable” overstates the position for most homes, and a poor rating still narrows your buyer pool in ways that weren’t true five years ago. We’ll explain what’s really going on with lenders and EPCs in 2026, which properties are affected, what you can do about the rating, and how to sell if improving it isn’t practical.
What “Unmortgageable EPC” Actually Means
No mainstream lender refuses to lend purely because a house has a low EPC band. What’s happened is more specific.
- Buy-to-let lenders increasingly decline, or lend on worse terms, for properties rated F or G, because landlords can’t legally let them without an exemption. Proposed changes would raise the minimum for rented homes to C by the end of the decade, and some lenders are already pricing for that.
- Some lenders apply higher rates or lower loan-to-value limits for E, F and G rated homes across the board, reflecting the cost of future improvements.
- Valuers note poor ratings and may reduce the valuation where the improvements needed are expensive, such as solid wall insulation on an older property.
- Buyers themselves look at the rating and the estimated running costs on the certificate, and many walk away from a G before they’ve seen the kitchen.
So the practical position is that a low rating makes a house harder to sell to a landlord, more expensive to mortgage for some owner-occupiers, and less attractive to everyone. For older, solid-walled, off-gas properties, the gap between the current rating and a comfortable one can cost tens of thousands to close.
Which Properties Tend To Rate Badly
If you own one of these, a poor rating comes as no surprise.
- Pre-1930s solid brick or stone houses with no cavity to insulate
- Properties heated by oil, LPG, electric storage heaters or open fires
- Homes with single glazing, uninsulated lofts and original timber floors
- Listed buildings and houses in conservation areas, where insulation and window changes are restricted
- Park homes, chalets and other lightweight structures
- Large detached rural houses with high heat loss and no mains gas
The assessor’s methodology rewards insulation, efficient heating and controls, and penalises everything else. A beautifully maintained Victorian terrace with original sash windows can rate E or F simply because of its construction.
Can You Improve The Rating Before Selling?
Sometimes cheaply, sometimes not at all.
Quick Wins
Loft insulation to 270mm, LED lighting throughout, a hot water cylinder jacket, draught-proofing and heating controls can each add points. On a borderline property, these alone can lift a band. They cost hundreds, not thousands.
Mid-Range Measures
Cavity wall insulation where there’s a cavity, replacing an old boiler with a modern condensing model, and double glazing make a bigger difference, at a cost that may or may not be recovered in the sale price.
Expensive Measures
Solid wall insulation, heat pumps, floor insulation and solar panels can transform a rating but routinely cost more than the uplift in value, particularly on a house you’re about to sell.
Getting A New Certificate
If you’ve made any improvements since the last EPC, commission a new assessment before marketing. Assessors can only record what they see evidence of, so have receipts, guarantees and installation certificates ready, and point out measures that aren’t visible, such as underfloor insulation.
Selling With The Rating As It Is
If improving the rating isn’t worth it, you have three main routes.
- Open market to owner-occupiers. Most owner-occupier lenders will still lend on an E, F or G rated home, so the market is there. Price realistically, be clear about the construction and heating, and expect buyers to factor in the improvement cost. Avoid marketing to landlords, who’ll struggle to get finance.
- Auction. Buyers in the room expect older, inefficient stock and bid accordingly. You get a binding sale on the day, with fees deducted and price risk accepted.
- Cash sale. A cash buyer isn’t concerned with lender EPC policies, because there’s no lender. The rating feeds into the price alongside everything else about the house. If you’d like a guaranteed sale for a low EPC rated house without spending on insulation first, we’ll make an offer within 24 hours based on the property as it stands. We cover the survey, the legal fees and the EPC itself, which is useful if your certificate has expired. Our offers fall between 70% and 85% of market value, and we buy across England and Wales.
If The Property Is Currently Let
An F or G rated rental property brings extra complications. Unless a valid exemption is registered, letting it is unlawful and you could face a penalty. That affects a sale in two ways: a buyer intending to let it on will need to improve it or register an exemption before they can, and a buyer’s solicitor will ask whether you’ve been letting it in breach.
If you’re selling a tenanted F or G rated property, be upfront about the rating and any exemption. Cash buyers who purchase tenanted stock will factor in the improvement cost and take on the compliance after completion, which is often the simplest route for a landlord who’d otherwise need to fund the work while still carrying the mortgage.
What The EPC Does To Your Price
The effect varies with the property type and the likely buyer. On a period house in a sought-after area, buyers expect a poor rating and the discount is modest. On a 1960s semi where a C is normal and yours is an F because of storage heaters and no loft insulation, the gap is larger because the improvements are obvious and the comparables are better rated. Across the board, the discount tends to track the realistic cost of lifting the rating to a level buyers are comfortable with, plus a margin for the hassle. Knowing that figure before you go to market, from an assessor’s recommendations or a couple of quotes, puts you in a far stronger position whichever route you choose.
FAQs
Can you get a mortgage on a house with an F or G EPC rating?
Owner-occupiers usually can, though some lenders charge more or lend less on low ratings. Buy-to-let lenders increasingly decline F and G rated properties because they can’t legally be let without an exemption.
Do I need a valid EPC to sell my house?
Yes. An EPC must be commissioned before marketing and provided to buyers. Certificates last ten years. If you sell to us, we cover the cost of a new one if yours has expired.
Will improving my EPC rating increase the sale price?
Cheap measures like loft insulation and LED lighting can lift a band at low cost and are usually worth doing. Expensive measures such as solid wall insulation or a heat pump rarely recover their cost in a sale.
Can I let a property with an F or G rating?
Not without a registered exemption. The minimum standard for rented homes in England and Wales is currently E, and proposals would raise it to C for new tenancies in the coming years.
Does a listed building need to meet EPC standards?
Listed buildings are often exempt from needing an EPC where compliance would unacceptably alter their character, but the exemption isn’t automatic. Check with your local authority or a specialist assessor.
Will a cash buyer purchase a house with a very low EPC rating?
Yes. The rating affects the offer alongside the property’s condition and location, but there’s no lender policy to satisfy, so a low band doesn’t prevent the purchase.