The deadline is closer than it looks
April 2028 is less than two years away — and for commercial landlords, it represents the single most significant regulatory shift in the history of energy efficiency legislation in England and Wales.
From that date, landlords will be prohibited from continuing to let any commercial property with an EPC rating below E. This is not just about new lettings: existing leases will be caught too. A tenant who signed a ten-year lease in 2021 will still be affected if their building falls below the threshold.
The legislation builds on the framework already in place since 2018, which required an EPC E minimum for new lettings. The 2028 change closes the loophole that allowed sub-threshold buildings to continue under existing leases.
What the standard actually requires
The threshold is EPC band E or above. In practice, that means an EPC score of 25 or higher on the 1–100 scale. Buildings rated F or G — typically scoring below 25 — will be unlettable without a valid exemption.
Exemptions do exist, but they are narrow. A landlord can apply for an exemption if all cost-effective improvements have already been made and the property still falls below E, or if improvements would devalue the property by more than 5%. Exemptions must be registered on the PRS Exemptions Register and last a maximum of five years.
Critically, "I didn't know" is not an exemption. Penalties for non-compliance run to up to £150,000 per property, depending on the length of breach and the property's rateable value.
Why now is the right time to act
The gap between now and 2028 feels wide. It isn't.
Retrofit programmes on commercial buildings take time. An EPC assessment, followed by a feasibility study, then procurement, then works — a typical cycle for a multi-asset portfolio runs 18 to 36 months even in ideal conditions. Contractors in the M&E and insulation trades are already reporting extended lead times as demand builds.
There is also a financial logic to acting early. Landlords who wait until 2027 will face a seller's market for retrofit works, with costs pushed up by urgency. Those who begin assessment now can plan CapEx across financial years, access green finance at more favourable terms, and use the improvement process as a leasing tool — not a fire drill.
The risk of stranded assets
Beyond the letting restriction, there is a growing body of evidence that energy-inefficient buildings are beginning to trade at a discount — the so-called "brown discount." Institutional investors, lenders, and occupiers are all incorporating EPC ratings into their decision-making. Buildings stuck at F or G are increasingly unlettable, unfinanceable, and unsaleable at previous values.
For landlords holding assets across a portfolio, the exposure is not uniform. Some buildings will require modest improvements — LED lighting, controls upgrades, boiler replacements — to cross the threshold. Others, particularly older stock with solid-wall construction or poor roof insulation, may require significant capital investment.
Understanding which assets are at risk, and in what order to prioritise intervention, is the first step.
How Building Atlas helps
Building Atlas was built for this problem. We take your portfolio of property addresses and produce a costed, prioritised retrofit plan — within 48 hours.
Our analysis combines EPC data, building-level energy modelling, contractor benchmarks, and regulatory trajectories to give you:
- A current EPC rating and projected 2028 compliance status for every asset
- Recommended improvement measures, ordered by cost-effectiveness
- CapEx estimates and indicative payback periods
- A portfolio-level view of total investment required and phasing options
You don't need to have a surveyor on your team or an energy consultant on retainer. You need a list of addresses and 48 hours.