EPC Changes 2025: What South London Landlords

From 15th June 2025 – a Sunday, randomly enough – get ready for new-style assessments when it comes to Energy Performance Certificates (EPCs).

If you’re a landlord here in South West London, it’s something to get your head around. I’m not here to scaremonger or dazzle you with acronyms – it is just a tweak to part of the marketing and letting process – but nevertheless, it is relevant to you as a landlord, so I am here tell you what’s changing, why it matters, and what you need to do to avoid your energy rating taking a potential nosedive.

What exactly is an EPC?

If you’re already an existing landlord, or if you’ve sold a property in the last – oh, goodness – 18 years or so, you definitely should already know what an EPC is.

As mentioned earlier, it is an ‘Energy Performance Certificate’, and it rates how energy efficient a property is, from A (most efficient) to G (least efficient). It is carried out by a qualified Domestic Energy Assessor, and it looks at things like insulation, heating systems, glazing, and energy use; it also provides suggestions for how to improve matters.

Any seller or landlord requires a valid EPC to rent or sell or let out a property; furthermore, it is a requirement for marketing, not something to complete ‘after the fact’.

Tenants have a right to see an EPC before they move in – and indeed, it is part of proscribed information that should be provided to a tenant when the tenancy is executed – at pain of invalidating any Section 21 Notice if one has not been provided along with other key documents (whilst Section 21 exists, of course… a blog for another day…).

For landlords, it’s more than just a legal requirement – it affects your property's appeal, running costs, and in some cases, whether you’re allowed to let it at all.

So, what EPC changes are coming in?

The way that EPCs are calculated is getting a major shake up. To get technical about things, we’re moving from RdSAP 2012 to RdSAP 10… which I accept will sound like so much jargon, so let me lay out what the change means.

It is really all about getting a more detailed and accurate picture of a property’s energy efficiency.

Until now, EPC assessors have often made a lot of assumptions when they the appropriate information was unavailable. No paperwork for your fancy new boiler? Let’s assume it is a bog-standard one. Can’t confirm your walls were insulated? Well, let’s mark them down as uninsulated.

As you can imagine, this hasn’t done many landlords many favours in many cases – especially if you have actually invested in the place.

The new method means assessors will be asking more questions, collecting more data… but also, they will be requiring more proof.

That means more paperwork for you. I know, no surprise there, right?

But it could in theory result in a fairer rating that actually reflects what your property has to offer – and there could therefore be benefits in rental value uplift and, ultimately, greater inherent value in the bricks and mortar whenever it is that you might come to sell or remortgage.

What kind of details will EPC assessors now need?

Assessors will now be collecting or verifying:

• The type and condition of your windows (glazing and frames)
• Your boiler's make and model, as well as its efficiency rating
• Evidence of insulation (walls, loft, floors)
• What sort of heating controls you’ve got – including any smart systems
• Whether you’ve got things like waste water heat recovery or mechanical ventilation

In short: if it affects heat loss or energy use, they want to know about it… in more detail than they have done thus far. Without paperwork though, if you can’t prove what energy efficiency benefits you have made through works undertaken, they may default to an assumption that brings the score in lower than your property deserves.

So what’s the risk?

If you’ve had an EPC done in the past and scored, say, a C – don’t assume that’ll hold up under the new regime. You might find your rating drops if you can’t provide the right documentation. And if you’re managing a portfolio, or looking to refinance, that could be a real spanner in the works.

That said, it’s not all doom and gloom. Properties that were previously penalised – particularly mid-terrace homes and flats that benefit from heat retention – might actually see their scores improve. The new model takes more account of thermal mass and actual heat loss areas, so it’s more accurate overall.

Will EPC assessments now cost more?

In a word: yes. I’m afraid it does look that way, from the correspondence we have received from domestic energy assessors.

The extra detail now required under RdSAP 10 means that assessors will be spending longer on site, taking more measurements, cross-referencing more evidence, and – in many cases – will require not only new tools but additional training to meet the new standards.

Unfortunately, that kind of uplift in work naturally comes with a price tag. We have been advised that EPC assessments are likely to cost at least 30% more going forward.

But on the other hand, bitter as that pill is to swallow, in theory – done properly – it is not just paying for a piece of paper; it is paying for accuracy, and a report that can genuinely help inform upgrades, access grants, and improve future compliance.

 

What do we recommend?

At Your Home Managed, we’re already speaking to our landlords about getting their ducks in a row. Here’s what we’re advising:

1. Get your paperwork together. That means invoices, installation records, user manuals, certificates – anything that proves what’s been fitted and when. If your boiler was swapped in the last ten years, find the paperwork.
2. Take photos – inside and out. Assessors may need to see your windows, insulation access points, thermostats and controls, or even loft insulation. If you can’t show it on the day, they’ll go with the lowest likely rating.
3. Speak to your managing agent. An agent like ourselves at Your Home Managed can help you prepare, connect you with trusted EPC assessors, and make sure you’re putting your best foot forward when it comes to the assessment.

Why it matters

An EPC isn’t just a box-ticking exercise – but perhaps that is how they have been treated, and this change is in part designed to tighten things and underline the importance in them.

I have to say, our own observation from an Agency point of view, is that tenants are more energy-aware than ever, and a low EPC rating can absolutely affect how attractive your property is. And of course, there are already minimum energy rating requirements for letting a property – nothing less than an E rating – and this is set to increase to ‘nothing less than a C rating’, by 2030.

Mortgage lenders are also tightening up – a property’s energy rating could be the difference in a mortgage offer being made or being held back.

It’s also a step towards net-zero – and I think, whether everyone adheres to net-zero as a policy or not, we can probably say that generally speaking we all tend to agree that the more environmentally friendly we can be the better.

At the end of the day, your EPC is a public document. It affects your marketability, your compliance, and potentially your returns. So yes, the new rules mean more legwork – but they’re also a chance to take stock and make sure your property is performing.

If you're a landlord in Streatham, Balham, Tooting or Colliers Wood and you're not sure where to start, give us a call. We’ll talk you through what’s needed – no nonsense, no jargon, and no unnecessary panic.