Landlord Guide: Reaching EPC C by 2030, and What New Windows Can (and Can't) Do

Private rented homes in England and Wales must reach an Energy Performance Certificate rating of at least band C by 1 October 2030. Where that cannot be achieved, the landlord must show they have spent up to a cost cap of £10,000 per property before registering an exemption. New windows are one of the most effective single measures towards band C, but they are rarely the whole answer, and this guide is honest about both halves of that.

The rule in plain English

• Deadline: 1 October 2030, for private rented homes in England and Wales, across all tenancies.
• Target: EPC band C (a score of 69 or more out of 100 on the current certificate).
• Cost cap: £10,000 per property, or 10% of the property's value if it is worth under £100,000. Eligible spending from 1 October 2025 counts towards it.
• If band C cannot be reached within the cap, the landlord registers an exemption. A property that misses the target without a registered exemption cannot legally be let.
• The reformed EPC (with its separate Fabric Performance score) has been delayed to the second half of 2027. That delay does not move the 2030 deadline. Our EPC guide explains the reform.

What new windows can do

Glazing is one of the inputs to the EPC score alongside insulation, heating and hot water. Across our Bristol, Exeter and Cardiff installations we typically see these improvements from a full set of A-rated or A++ windows: replacing single glazing adds 15 to 28 points; replacing pre-2002 double glazing (old sealed units with no low-emissivity coating) adds 8 to 18 points; upgrading post-2002 double glazing to A++ units adds 5 to 10 points.

The gap between the middle of band D and the bottom of band C is usually 10 to 15 points. So a property with single glazing or tired early double glazing that sits in the top half of band D can often reach C on windows alone. That is the best case, and it is common in Victorian and Edwardian terraces across Bristol, Newport and Cardiff where the original windows or a 1990s replacement are still in.

What new windows can't do

If the property is at the bottom of band D or in band E, windows will not get you to C by themselves. Solid walls with no insulation, an uninsulated loft, an old boiler or electric panel heaters each cost more EPC points than glazing can recover. In those homes the sensible order is loft insulation first (cheapest points), then heating, then windows, and the assessor's recommendations report on the existing certificate tells you which measures move your specific property the most. We will say so at the survey rather than sell you windows that leave you short.

What it costs, and the cap

A typical three-bedroom rental with eight windows can be upgraded to A++ double glazing for around £3,500 to £5,500, and a whole-house replacement in our Eco Flush range typically runs £4,500 to £7,500 depending on sizes and specification. Both sit comfortably inside the £10,000 cap and leave room for insulation. Windows and doors are charged at 20% VAT; the 0% rate for energy-saving materials does not cover them. Every installation is FENSA registered (39576), which gives you the compliance certificate the EPC assessor and your local authority will want to see, and is covered by our 15-year guarantee with Installsure insurance backing.

For portfolio owners we offer landlord packages with volume pricing and a phased programme, so several properties can be surveyed together and fitted in order of tenancy renewals. Flexible finance is available, subject to status, arranged through Phoenix Financial Consultants.

Wales

The 2030 deadline and the cost cap apply in Wales as they do in England. Our Cardiff office and the team covering Newport, Chepstow and the wider South Wales area handle landlord work across the CF and NP postcodes, with free surveys and the same 15-year guarantee.

A sensible plan for the next four years

• Pull the current EPC for each property from the register and note the score, not just the band.
• Read the recommendations on each certificate: they are ordered by impact for that property.
• Run our free EPC calculator to see roughly what new windows would add.
• Book a free survey. Our surveyor will tell you whether windows alone reach C, or what needs to go with them.
• Keep every receipt from 1 October 2025 onwards: it all counts towards the cap.
• Schedule work around tenancy changes so voids are short and tenants are not disrupted mid-winter.