Major changes to EPCs coming in 2026

Reply to the comment left by Peter Merrick at 12/02/2025 – 16:22
Solar panels may fall in price, but the largest part by far of the cost now is the labour to fit them, plus business costs like paperwork, corporation tax, transport cost and time, etc and the need for the business owners to take an income. And atomised single householders will always pay much more than multi-unit housebuilders – economies of scale and bargaining power always win.

So green zealots can bleat all they like about the cost of panels falling by 90%. So what? All I know is that I was quoted £5500 to install 4kW of solar panels on my private home in 2015, and £8500 in 2023. Where are these mythical falling prices? And when I worked or a housebuilder on a 150-unit new-build estate in 2021-2023, their cost for 4kW was £3300. Go figure.

Reply to the comment left by AnthonyJames at 12/02/2025 – 23:09
I’ve looked into this as well and again I haven’t seen much evidence of pricing coming down from people advertising a service to install them. I can’t see that coming down either with employers’ NI going up.

The last time I looked at solar panels you could do it yourself but whether it was worth the effort is debatable because if you do it yourself you don’t get any warranty. A friend of mine has installed DIY panels but he’s done it for energy security reasons…power backup. I doubt that any landlord can consider DIY because it’s an electrical item and you’d probably be obliged to keep paperwork saying it had been installed by a registered installer.

I think probably DIY will grow as there seem to be new kits coming onto the market.

https://www.sunstore.co.uk/product-category/solar-panel-kits/diy-solar-systems/?srsltid=AfmBOorRsBwVoui32vZMkKcjqW9sRLxSWaWFm24Lc8neLfBrYpStQ6Ka

Reply to the comment left by Darren Peters at 12/02/2025 – 14:41
My understanding is that thermal imaging cameras can see the actual wall temperature and can see the difference between insulated walls and non-insulated walls. When I last had one pointed at a wall without CWI the areas of heating loss were obvious….not the wall but the windows. And when you opened a window or a door. I don’t know if anybody else has tried to challenge an EPC assessor or assessment company using this technology successfully. But if it hasn’t been permitted then it should be permitted.

EPC assessors, companies assessing properties for grants and the system itself have a bias towards CWI. But CWI can be damaging. It can cause problems with damp especially if your property has traditional building materials, limestone mortar and/or plaster and perhaps no modern damp-proof course. And if CWI stops your floors ventilating it can cause floor joists to rot.

For many EPC assessors including CWI seems to be a knee-jerk response. If you can prove that this is not where you are losing your heat then you ought to be able to challenge this and spend your money where it makes a positive difference to both you and the tenants.

Reply to the comment left by Beaver at 13/02/2025 – 10:06
Yes, DIY is attractive and it is permitted: all you need is a registered electrician to connect to the smart meter and sign it off (the main cost). There will be a chunk of paperwork registering with the DNO to permit exporting, if you want to do this. Myself, I can’t see the point as the payments are so paltry, but you do need a place to direct your surplus energy. This could be an ASHP or an electric battery – another hefty expense but it and a variable-rate tariff make sense if you are going to use solar panels effectively. The battery can also be charged cheaply at night from the mains, releasing power during the day to reduce your draw-down on the Grid and your costs.

Or your “battery” could be a hot water tank, which your surplus solar power goes to heat, like an immersion heater.

What I haven’t yet found is a real-world, believable account of typical cost savings by a British DIYer or ten. This and a list of gotchas would be very useful to assess if a DIY job is worthwhile and within one’s scope of expertise.

Reply to the comment left by Beaver at 13/02/2025 – 12:34
EPC assessors like CWI because that’s an easy win in their CAD software. They’re not concerned with the detail of thermal bridges or damp.

Thermal cameras are no panacea: there are good ones and rubbish ones. Could anyone really trust a thermal camera app on a mobile phone? Who calibrates and validates this? A good energy assessor however should be able to measure your overall heat energy inputs and outputs and come up with a measure of your losses and your building’s U-values. More importantly they should be able to advise on remedial works to fix cold bridges and – perhaps with a QS – come up with a plan to add insulation most effectively in terms of financial cost and gain in EPC points.

But then comes the practice after the theory. Who checks the work’s been done correctly and effectively, who guarantees the work, who produces the proof that is needed to recalculate your EPC value? Very tricky as the EPC is so subjective.

Reply to the comment left by AnthonyJames at 13/02/2025 – 14:02
All good points but it was a commercial quality thermal camera, not a mobile phone. I would definitely recommend it as I learned a lot from it. It’s easy to accept the assumptions of so called “experts”, especially as you correctly point out they are just plugging assumptions into their computer software and following their formula.

“C**p in = c**p out”.

Before reforming EPCs perhaps the government should get its own house in order?

https://www.whatdotheyknow.com/request/eir_request_epc_dec_display_ener_4#outgoing-1787556

Reply to the comment left by Beaver at 13/02/2025 – 14:52
Thermal imaging camera – were you working with an energy assessor or hiring/buying one yourself? Which model?

What amazes me about EPC assessment is the many reports about how unwilling they to accept evidence of completed works. They may accept there is cavity wall insulation if they see the drill holes – of course with no validation that it was done competently or how long ago – but you hear of people who have contractor plans, photographs and receipts showing internal or external wall insulation, or underfloor insulation, and the EPC applicant is told “this could be for another house” or “maybe you used a different insulation material”.

This is why anyone undertaking big expensive projects like IWI or EWI to achieve significant uplifts in their EPC ratings must get the work validated by a qualified third party: an energy assessor, local authority Building Control, or hire a private building inspector.

The latter has the advantage that not only will you also get adequate proof that your contractor is following building regulations, but also you’ll have a professional on your side checking the quality of the workmanship.

Reply to the comment left by AnthonyJames at 14/02/2025 – 09:37
I didn’t buy one. I was working with an assessor and the results were a revelation. It was the windows where the investment was needed, not the walls.

Reply to the comment left by John Jones at 14/02/2025 – 09:02
The let on number 10 Downing Street is a short-term let and the tenants probably aren’t going to be there when the EPC deadline kicks in.