Energy Performance Certificates (EPCs) are a legal requirement for landlords in the UK, and they play an increasingly important role in the rental market. As environmental standards tighten, landlords must not only comply with current regulations but also prepare for more stringent future targets.
Since 2008, all rental properties have needed an EPC before being advertised. The certificate – which is valid for 10 years from the date of assessment – gives a property an energy efficiency rating from A (most efficient) to G (least efficient) and includes recommendations for cost-effective improvements. Currently, landlords must ensure their properties meet a minimum rating of E. However, government proposals aim to raise this requirement to C for new tenancies by 2028, and potentially for all tenancies by 2030.
How are EPC ratings calculated?
EPC ratings are derived from the Standard Assessment Procedure (SAP), the UK government’s approved method for assessing energy performance in dwellings. The SAP score is a numerical value between 1 and 100+, representing the estimated cost of heating, lighting, and hot water. The higher the score, the more efficient the property.
This SAP score is then converted into the A – G band:
- A (92-100) – Most efficient
- B (81-91)
- C (69-80)
- D (55-68)
- E (39-54)
- F (21-38)
- G (1-20) – Least efficient
Even small improvements – just 1 or 2 SAP points – can push a property into a higher rating band, improving marketability and regulatory compliance.
Typical SAP score gains from common improvements.
Here are some examples of how much a typical improvement might increase your SAP score, though actual results vary depending on the property’s size, age, and current condition:
- Loft insulation (100mm → 270mm): +6 to 10 SAP points
- Cavity wall insulation: +5 to 10 SAP points
- Upgrading boiler to condensing model: +5 to 12 SAP points
- Installing TRVs or smart thermostat: +2 to 4 SAP points
- Switching all lighting to LEDs: +1 to 3 SAP points
- Replacing single glazing with double glazing: +2 to 6 SAP points
- Installing solar PV (e.g. 2kW system): +5 to 10 SAP points
- Air Source Heat Pump (replacing electric heating): +10 to 20+ SAP points
Understanding the points impact helps landlords prioritise high-value improvements that could shift a property from, for example, a D (68) to a C (69) with relatively low effort.
What improvements are worth making?
It’s worth considering possible energy efficiency improvements as part of any wider work that’s being done on the property. Improvements could include:
- Loft and Wall Insulation
Affordable, straightforward, and highly effective. Many older properties lack sufficient insulation and benefit immediately. - Heating System Upgrades
Replacing an outdated boiler or electric storage heaters with a modern condensing boiler or low-carbon system can significantly boost the score. - Windows and Glazing
Double or even secondary glazing improves thermal performance and tenant comfort, though it’s pricey. - Efficient Lighting
A quick win. Replacing old bulbs with LEDs is low-cost and measurable in SAP improvements. - Renewable Technology
Solar panels or heat pumps can be excellent long-term investments—especially when paired with government incentives or grant schemes.
Why it matters.
Improving your EPC rating is more than a compliance issue – it’s also about protecting your investment. A better-rated property is easier to rent, cheaper to run, and more resilient to future regulation. Landlords should look to use their EPC report to identify tailored, cost-effective actions – and not underestimate the value of even small upgrades.
As part of our management service options we organise and maintain EPCs to ensure compliance. Our local EPC Assessors can also advise on cost-effective measures that you might consider to get you the points required to raise the EPC rating of your property.
