Guide · 20 July 2026

The £10,000 cost cap and £30,000 fines, explained

How the proposed EPC C cost cap works for landlords: what spending counts, when an exemption applies, how the penalty regime stacks, and worked examples.

Two numbers dominate every conversation about the 2030 EPC C requirement: the £10,000 cost cap and the £30,000 maximum fine. Both are usually quoted without explanation. Here’s how they actually work.

The cost cap: a ceiling, not a bill

The cost cap is the most a landlord can be required to spend on qualifying energy improvements per property. It is not what most properties will cost — it’s the ceiling at which the obligation stops.

The mechanics:

  1. You improve the property, working through recommended measures.
  2. If it reaches C before you hit the cap — done, and most D-rated homes get there for a fraction of £10,000.
  3. If you spend to the cap and the property still can’t reach C, you register an exemption and can continue letting it lawfully.

What typically counts toward the cap: insulation (loft, cavity, internal or external wall), heating upgrades, hot water cylinder measures, glazing, draught-proofing, low-energy lighting, and associated surveying costs. Keep every invoice — the exemption case is built on the paper trail.

Where the money actually goes

Rough shape of the common measures (every property differs; these are orientation figures, not quotes):

MeasureTypical rangeTypical EPC impact
Loft insulation top-up£300–£700Small but cheap
Cavity wall insulation£1,000–£3,000Significant
Internal wall insulation (solid walls)£5,000–£12,000+Large — often the decisive measure on period stock
Heating controls / boiler upgrade£400–£3,500Moderate
Double glazing£3,000–£8,000Moderate

The pattern: modern cavity-wall stock usually reaches C cheaply; solid-wall period property is where the cap matters, because internal wall insulation alone can approach it. That’s also why those works want a void — they’re intrusive with a tenant in place.

The fines: how the exposure stacks

The proposed regime allows penalties of up to £30,000 per property for non-compliance. Notice the phrase per property: for a portfolio landlord — or an agent whose managed book carries dozens of D-and-below homes — the theoretical exposure multiplies fast. Today’s MEES regime (the E floor) already carries fines up to £5,000 per property plus publication of the breach, so the enforcement machinery exists; 2030 raises the stakes rather than inventing them.

The rational strategy

Because the cap creates a defined worst case, every property has a knowable position: reaches C for £X or caps out and exempts. That means a portfolio can be planned — surveyed early, costed early, and the works sequenced across natural void periods between now and 2030 so no rent is lost and nothing is done in a panic.

That plan is exactly what our free assessment produces: each property’s rating, its likely route to C, and a forward schedule mapped to tenancy end dates. Start with the assessment — it commits you to nothing.

Figures reflect the consultation position as of July 2026; final regulations may adjust detail. The structure — capped spend, registered exemptions, per-property fines — has been stable throughout.


My EPC Partner maps portfolios against these rules for free — every property's rating, expiry, and route to C, scheduled to your voids. Book the free assessment.