Energy Performance Certificate (EPC) Explained – Ratings, Costs, Rules & How to Improve Your Home’s Energy Efficiency

An Energy Performance Certificate (EPC) rates the energy efficiency of a domestic dwelling in the UK. It provides homeowners, landlords, and buyers with essential information about how energy efficient a property is, how much energy it consumes, and the estimated cost of running it. 

At Daylight Glazing, we help homeowners and landlords improve their EPC rating through energy-efficient windows, doors, glazing, and conservatories, one of the most effective upgrades for boosting energy performance. 

What Is an Energy Performance Certificate (EPC)?

An Energy Performance Certificate is an official document that rates a property’s energy efficiency on a scale from: 

A – the most energy efficient 

G – the least energy efficient 

The average EPC rating in the UK is Band D, meaning most homes still have significant room for improvement. 

Each EPC contains:

The current energy rating of the house

The potential energy efficiency rating

Estimated annual energy bills

Clear recommendations for improving energy efficiency

Energy Performance Certificate (EPC) Explained – Ratings, Costs, Rules & How to Improve Your Home’s Energy Efficiency  | Daylight Glazing

What Information Does an EPC Include?

The EPC provides a breakdown of: 

  • How much energy a property uses
  • Typical heating, lighting, and hot water costs
  • Environmental impact and CO₂ emissions

Common EPC Recommendations

  • Low energy light bulbs
  • Double glazing with Low-E glass
  • External and internal wall insulation
  • Loft and solid floor insulation
  • Solar water heating

Many of these improvements—especially energy-efficient glazing and doors—can significantly improve your EPC score. 

Energy Performance Certificate (EPC) Ratings Explained (A–G)

Residential properties are rated from A to G: 

EPC Rating    Meaning 

A–B               Highly energy efficient 

C               Good energy performance 

D               UK average 

E               Minimum acceptable for rentals 

F–G                Poor efficiency, high energy costs  

Improving windows, doors, and insulation can move a home up one or more EPC bands. 

How Is an EPC Calculated?

An EPC assessor will inspect: 

  • Windows and doors 
  • Insulation levels 
  • Heating systems 
  • Hot water efficiency 
  • Lighting 
  • Glazing performance (double or triple glazing) 

When Was the EPC Introduced?

The EPC was introduced in 2007 as part of the Home Information Pack (HIP). Although HIPs were discontinued in 2010 due to criticism for slowing housing sales, the Energy Performance Certificate remained a legal requirement for sellers and landlords. 

Minimum EPC Rating Requirements for Rental Properties 

Since April 2020, rental properties must achieve a minimum EPC rating of E 

Government proposals announced in 2021 aim to require: 

  • All new rental properties to be EPC C by December 2025 
  • All existing rental properties to reach EPC C by December 2028 

When Do I Need an EPC?

1-You DO need an EPC if: 

✔ You want to sell your house (the seller must provide it) 

✔ You build a new house 

✔ You’re a landlord renting to a new tenant 

2-You DON’T need an EPC if: 

✖ You’re buying a house (the seller pays) 

✖ You have a lodger 

✖ You’re a tenant (the landlord is responsible) 

Energy Performance Certificate (EPC) Explained – Ratings, Costs, Rules & How to Improve Your Home’s Energy Efficiency  | Daylight Glazing

Buildings That Are Exempt from EPCs

The following buildings do not require an EPC: 

  • Listed buildings 
  • Buildings used for less than two years 
  • Holiday accommodation let for under four months per year 
  • Residential buildings used less than four months per year 
  • Stand-alone buildings under 50m² 
  • Buildings due to be demolished 
  • Workshops and agricultural buildings with low energy use 
  • Places of worship 

How to Improve Your EPC Rating

1-Upgrade to Energy Efficient Windows 

Replacing old windows with double or triple glazing significantly reduces heat loss. 

Benefits include: 

  • Higher window energy rating 
  • Lower heating bills 
  • Improved EPC band 

2-Install Energy Efficient Front & Exterior Doors 

Modern insulated doors prevent heat escaping and improve overall energy performance. 

3-Improve Conservatory Energy Efficiency 

Upgrading conservatory glazing and roofing helps prevent heat loss and boosts EPC ratings. 

Why Choose Daylight Glazing to Improve EPC Ratings?

High-performance double & triple glazing

Aluminium & uPVC energy-efficient windows

Energy-rated front and exterior doors

Low-E and energy-saving glass

Heritage and modern glazing solutions

Improving your glazing is one of the fastest and most cost-effective ways to raise your EPC rating. 

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Conclusion

An Energy Performance Certificate is more than a legal requirement—it’s a roadmap to:

  • Lower energy bills 
  • A more comfortable home 
  • Higher property value 
  • Compliance with future EPC regulations 
If you want to improve your EPC rating, Daylight Glazing can help you achieve it with expert glazing and energy-efficient solutions

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FAQs

An EPC is valid for 10 years, unless major energy-efficiency improvements are made earlier. 

The typical EPC cost in the UK ranges between: 

  • £60 – £120 for domestic properties 

Prices depend on property size and location. 

Yes — most of the providers above let you get an instant online quote and arrange an EPC booking in seconds, without needing phone calls or estate agent involvement. 

  • Domestic EPCs are for homes and flats. 
  • Commercial EPCs are for non-domestic buildings like offices, shops, and warehouses and use a more detailed assessment method. 
  • Domestic EPCs are for homes and flats. 
  • Commercial EPCs are for non-domestic buildings like offices, shops, and warehouses and use a more detailed assessment method.