EPC Certificate UK

EPC Rating G — The Lowest Energy Performance Rating

EPC Rating G is the lowest energy efficiency rating for UK properties. Learn what it means, typical energy costs, why properties get rated G, and how to improve to a higher band.

EPC Rating G means your property has the poorest energy efficiency, with a SAP score of 1-20 points. Properties with this rating typically have high energy bills and significant heat loss.

What Does EPC Rating G Mean?

An EPC Rating G indicates your property falls into the lowest band on the Energy Performance Certificate scale. With a SAP (Standard Assessment Procedure) score between 1 and 20 points, G-rated properties are the least energy efficient homes in the UK.

Properties with an EPC G rating typically cost £3,000-£5,000+ per year to heat and power — often double or triple what better-rated properties cost. These homes lose heat rapidly and require constant heating in winter to maintain comfortable temperatures.

Typical Characteristics of EPC G Properties

  • No insulation: Little to no loft insulation, no cavity wall insulation
  • Single glazing: Original single-pane windows throughout
  • Old heating system: Inefficient boiler (G-rated or worse) or electric storage heaters
  • Solid walls: Uninsulated solid brick or stone walls (common pre-1920)
  • Draughty: Gaps around windows, doors, and floors
  • No heating controls: No thermostat or timer controls

Why Properties Get Rated EPC G

Most G-rated properties are older homes that haven't been modernised:

  • Victorian terraces with original features intact
  • Rural cottages with solid stone walls
  • 1960s-1970s properties with electric heating
  • Listed buildings where improvements are restricted
  • Properties that have been empty or neglected

Can You Rent Out an EPC G Property?

No, EPC G properties cannot legally be rented out. Since April 2020, the Minimum Energy Efficiency Standards (MEES) require all rental properties to have at least an EPC E rating. Landlords face fines up to £5,000 for non-compliance.

How to Improve from EPC G

The good news: G-rated properties often see the biggest improvements from basic upgrades. Priority improvements include:

Quick Wins (Under £500)

  • Loft insulation: £300-400, can jump 5-10 EPC points
  • Draught proofing: £200-300, adds 1-3 points
  • Hot water cylinder jacket: £20-30, adds 1-2 points
  • LED bulbs throughout: £50-100, adds 1-2 points

Medium Investments (£500-£3,000)

  • Cavity wall insulation: £500-1,500, adds 10-15 points
  • New boiler: £2,000-3,000, adds 10-20 points
  • Heating controls: £200-400, adds 2-4 points

Major Upgrades (£3,000+)

  • Double glazing: £3,000-7,000, adds 5-10 points
  • External wall insulation: £8,000-15,000, adds 15-25 points
  • Solar panels: £5,000-8,000, adds 5-15 points

Costs of Living in an EPC G Property

Property Type Typical Annual Energy Cost vs EPC C Property
1-bed flat £1,800-2,500 +£1,000-1,500
2-bed house £3,000-4,000 +£1,800-2,500
3-bed house £4,000-5,500 +£2,500-3,500
4-bed house £5,000-7,000 +£3,000-4,500

Should You Buy an EPC G Property?

G-rated properties often sell at a discount, but factor in:

  • Immediate costs: Budget £10,000-20,000 for essential improvements
  • Mortgage issues: Some lenders won't lend on G-rated properties
  • Running costs: Expect high energy bills until upgraded
  • Potential: Often the best properties to add value through renovation

Positive Outlook

While EPC G is the lowest rating, these properties often have the most potential for improvement. Basic insulation and a new boiler can easily lift a G-rated property to E or D, significantly reducing energy costs and increasing property value.

Frequently Asked Questions

What does EPC rating G mean?
EPC rating G is the lowest energy efficiency rating on the Energy Performance Certificate scale, with a SAP score of 1-20 points. Properties with this rating have very poor insulation, inefficient heating systems, and typically cost £3,000-5,000+ annually in energy bills.
Can I rent out a property with EPC rating G?
No, you cannot legally rent out an EPC G property. Since April 2020, the Minimum Energy Efficiency Standards (MEES) require all rental properties to have at least an EPC E rating. Landlords can face fines up to £5,000 for renting out G-rated properties.
How much does it cost to improve from EPC G?
Basic improvements costing £2,000-5,000 (loft insulation, draught proofing, new boiler) can often lift a G-rated property to E or D. More comprehensive upgrades including double glazing and wall insulation might cost £10,000-20,000 but could achieve a C rating.
Is it worth buying a house with EPC rating G?
G-rated properties can be good investments if you budget for improvements. They often sell at a 5-10% discount but require £10,000-20,000 in upgrades. Some mortgage lenders won't lend on G-rated properties, so check financing options first.
What are typical features of an EPC G property?
EPC G properties typically have no loft insulation, single glazing, solid uninsulated walls, old inefficient boilers, and no heating controls. Most are older properties built before 1920 or houses with electric storage heaters that haven't been modernised.