EPC C by 2030: What the Proposed Minimum Means for London Landlords

The government has proposed raising the minimum EPC for rental properties to band C, by 2028 for new tenancies, 2030 for all. The legislation is not yet passed, but the policy direction is consistent and firm. London landlords with sub-C properties who act now avoid the 2027–2028 installer rush and may access ECO4 funding that will not be available later.

The legislative timeline

The EPC C minimum has been in development since 2021:

The dates have slipped from the original 2025 proposal, but 2028 has remained consistent for three years across political changes. Most property solicitors and letting agents are treating 2028 as a firm planning horizon.

What reaching C means for different London property types

Band C starts at 69 SAP points. The gap from your current rating:

Cavity-wall properties (1920–1990 builds)

Properties in Ealing, Bromley, Enfield, Croydon, Barnet, Sutton, and Havering built between the 1920s and 1990s. These are the most straightforward to upgrade:

• Cavity wall insulation: £400–£800, +5–10 SAP points
• Loft insulation to 270mm: £400–£600, +4–8 SAP points
• LEDs: £80–£150, +2–4 SAP points
• Estimated total to reach C from D: £800–£2,200

Many properties qualify for ECO4 or GBIS, potentially free. There is no strong financial reason to delay for these properties. Do it now, between tenancies, and re-let at the higher standard.

Victorian and Edwardian solid-wall properties (pre-1919)

The high-risk category. Inner-London stock in Hackney, Islington, Lambeth, Wandsworth, Southwark, and Tower Hamlets:

Option 1, External wall insulation (EWI): Rendered insulation board on the outside. Adds 10–18 SAP points. Cost for a London mid-terrace: £12,000–£18,000. Planning consent typically required for front elevation; conservation areas may restrict EWI entirely.

Option 2, Internal wall insulation (IWI): Dry-lining on the inside of external walls. Similar point gain to EWI. Cost: £8,000–£14,000. Reduces floor area and disrupts interior finishes.

Option 3, Solar PV: A 3.5kWp south-facing system adds 12–18 SAP points. Cost: £6,000–£9,000. For Victorian terraces already at D63–D68, solar PV alone may be sufficient to reach C without wall insulation. The most cost-effective single measure for properties in this position.

Option 4, Combination (LED + loft + modern boiler): If the boiler is pre-2005, replacing it adds 6–8 points on top of lighting and loft gains. A Victorian terrace at D65 with an old boiler can reach C for £3,000–£5,000 via boiler + loft + LEDs, without touching the walls.

Estimated total to C for solid-wall Victorian: £3,000–£18,000, depending on current SAP score and route chosen.

The £15,000 cost cap and what it means for exemptions

The proposed C standard replaces the £3,500 cost cap (under the current E standard) with a £15,000 cap per property. This has a significant impact on exemptions:

A solid-wall terrace where EWI costs £14,000 may or may not qualify for exemption under the £15,000 cap depending on whether other recommended measures push the total above the threshold. Solar PV at £6,000–£9,000 plus other insulation measures may collectively clear C without requiring wall insulation, avoiding the exemption question entirely.

The exemption process mirrors the current MEES framework: three installer quotes, sub-cap measures completed first, registration on the PRS Exemptions Register. The evidence burden is the same; the financial threshold is much higher.

Why acting before 2027 makes financial sense

Installer capacity constraint: Independent analysis by Elmhurst Energy and CIBSE estimates the UK insulation and heat pump installation workforce is insufficient to upgrade 1.3 million sub-C rental properties by 2028. Prices will rise and availability will tighten from 2026 onward as awareness grows. Early movers get better pricing and faster scheduling.

ECO4 availability: ECO4 currently funds insulation for eligible households. The scheme closes in 2026 with a successor scheme expected but not confirmed. Landlords with eligible tenants who don't apply now risk paying full commercial cost later.

Between-tenancy efficiency: Insulation, EWI, and solar works are significantly simpler and faster in a void property. Coordinating improvement works around a sitting tenant adds cost, time, and friction. Every improvement done between tenancies avoids a disrupted tenancy.

Mortgage terms: Some lenders, including NatWest, Halifax, and Barclays' buy-to-let products, offer preferential interest rates for properties rated C or above. A portfolio refinance on C-rated stock vs D-rated stock can deliver 0.1–0.3% rate improvement, meaningful over a 5-year fix on a large portfolio.

Practical planning guide

Step 1: Check every property on the EPC register. Note the SAP score (not just the band letter) for each property.

Step 2: Group by property type, cavity-wall, solid-wall, flat, HMO.

Step 3: Commission assessments for any property without a current EPC. The assessment tells you the exact SAP score and what improvements would move you to C.

Step 4: Check ECO4 eligibility for all tenanted properties. Apply now if eligible.

Step 5: Schedule works by tenancy cycle. Use void periods for larger works.

For the full improvement cost breakdown, see our EPC improvement guide. For landlord compliance details, see our EPC for landlords guide. For MEES detail, see our MEES regulations guide.

We cover all London boroughs and offer portfolio assessment scheduling. Contact us or see our pricing page.