What Is An Energy Performance Certificate?

You’ll need an energy performance certificate if you’re buying, selling or renting property in the UK. Learn more about EPC ratings today.

If you’re building, buying, selling, or renting a property in the UK, you’ve likely come across the term Energy Performance Certificate (EPC). But what exactly is it, and why does it matter for homeowners, developers, and renovators?

In this guide, we’ll break down the essentials of EPC certificates and explain how choices like high-performance timber windows and doorsfrom Dale Joinery can make a real difference.

What Is an EPC?

An Energy Performance Certificate (EPC) rates the energy efficiency of a property on a scale from A (most efficient) to G (least efficient). It’s a legal requirement when building, selling, or renting a home and is valid for ten years.

The certificate includes:

Your property’s current energy rating and potential rating

Estimated energy use and costs

Recommendations for improving energy efficiency (e.g. better insulation or double glazing)

What EPC Ratings Mean

Each band is determined by a property’s energy use and carbon emissions, and can directly impact running costs and market appeal.

Here’s what each rating typically represents:

EPC Rating A: Exceptional efficiency

A-rated homes are rare and extremely energy-efficient. They often feature advanced insulation, renewable energy systems, and ultra-low running costs. Most new builds must now strive toward this standard.

Ideal for: Eco-conscious homeowners and future-proofed developments.

EPC Rating B: Very efficient

Properties with a B rating are well insulated with efficient heating and quality windows and doors. These homes are cheaper to run and tend to attract higher resale or rental values.

EPC Rating C: Above average efficiency

This is the UK government’s target standard for all homes by 2035. C-rated homes may still benefit from upgrades like improved glazing or loft insulation, but already perform reasonably well.

Common in homes with good-quality windows and a reasonably modern boiler.

EPC Rating D: Average efficiency

Many UK homes currently fall into this category. While not poor, D-rated homes could see significant energy and cost savings by improving insulation, switching to modern heating, or upgrading windows and doors.

EPC Rating E: Below average efficiency

Homes rated E tend to lose heat quickly and cost more to run. Upgrades are usually required before selling or renting under the current regulations for landlords.

Often lacks proper insulation and uses outdated glazing or single-pane windows.

EPC Rating F: Poor efficiency

Significant improvements are needed in F-rated properties to meet modern standards. These homes are typically cold, draughty, and expensive to heat.

Upgrading to modern timber windows and insulated doors can make a noticeable difference.

EPC Rating G: Very poor efficiency

The lowest rating. G-rated properties are often unmodernised and unsuitable for letting without major retrofitting. Heating costs are extremely high, and comfort levels are low.

A complete refurbishment is usually needed, including insulation, glazing, and heating upgrades.

Why Is It Important?

EPCs aren’t just about ticking a legal box; they provide valuable insight into how energy-efficient a property is. A better EPC rating can mean:

Lower energy bills

Improved property value

Enhanced comfort and warmth

Greater appeal to buyers or tenants

For developers, particularly in the new-build sector, a strong EPC rating can also help meet building regulations and planning conditions.

What Affects Your EPC Rating?

Several factors impact a property’s EPC rating, including:

Type and condition of insulation

Efficiency of heating systems

Glazing type and window performance

Air tightness

Renewable energy use (solar panels, heat pumps, etc.)

One of the most overlooked factors is the performance of windows and doors, where up to 25% of heat loss can occur.

How Dale Joinery Helps Improve Energy Performance

At Dale Joinery, energy efficiency is built into the design of every product.

Engineered Timber Construction

Our multi-layered timber offers greater stability and durability than solid wood, with improved thermal performance. It prevents warping and draughts, ensuring long-term insulation.

High-Performance Glazing

All Dale windows and doors feature double glazing as standard, with low-emissivity (Low-E) coatings and argon-filled units to reduce heat transfer.

Excellent U-Values

Our products meet or exceed the requirements set by Building RegulationsPart L, contributing significantly to a better EPC score.

Airtight Design

Precision manufacturing and factory finishing ensure a tight, secure fit - minimising air leakage and keeping cold draughts at bay.

Whether You're Renovating or Building New

Investing in high-performance timber windows and doors from Dale Joinery not only enhances the character of your home but also plays a key role in improving energy efficiency and boosting your EPC rating. It’s the ideal combination of beauty, compliance, and long-term value.

Ready to Improve Your Property's Performance?

Explore Dale Joinery’s full range of made-to-measure timber windows and doors and see how design-led sustainability can transform your next project.

Download our digital brochureor get in touchwith our team to discuss your project.