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Energy Rated Windows

BFRC Energy Rating for Windows

You may have seen in the media that new legislation is being introduced regarding energy ratings for windows. (At this stage, doors are not included.)

What is the BFRC Energy Rating?

The British Fenestration Rating Council (BFRC) is a government-backed initiative aimed at reducing energy consumption in residential properties. Working with European partners, the BFRC developed an Energy Rating Scheme specifically for windows, similar to the A–G energy labels used for household appliances like fridges and washing machines.

Since April 1, 2006, the BFRC Energy Rating has been incorporated into Building Regulations Part L for England and Wales. Compliance with these regulations is required for replacement windows and new windows in home extensions.

What Are the Required Energy Ratings?

  • Replacement windows must achieve an E Rating or better
  • New windows in extensions must achieve a D Rating or better

Previously, our standard windows—when fitted with Low-E glass—complied with Document L regulations and achieved a U-Value of <1.7 W/m²K. However, with new A, B, and C-rated options, we can now offer even better insulation with U-Values as low as <1.4 W/m²K.

Why Choose Energy-Rated Windows?

Our certified energy-rated window frames provide superior insulation, helping to:
✔ Lower your heating bills
✔ Improve home energy efficiency
✔ Reduce carbon emissions

For more details on the benefits of energy-efficient windows, visit the BFRC website.

A Rating – Eco Classic/Contour

  • U VALUE 1.4
  • REHAU S706 / Edge PVCu frame system with full reinforcement
  • 4-20-4 Low E 0.04 uncorrected emissivity
  • Inner pane (Saint Gobain Planitherm Total)
  • 90% Argon Gas, 10% Air filled
  • Low Iron outer pane (Saint Gobain Daimont)

Swisspacer V spacer bar with 3mm Polyurethane secondary seal

B Rating – Eco Classic/Contour

  • U VALUE 1.5
  • REHAU S706 / Edge PVCu frame system with full reinforcement
  • 4-20-4 Low E 0.04 uncorrected emissivity
  • Inner pane (Saint Gobain Planitherm Total)
  • 90% Argon Gas, 10% Air filled
  • Float Glass outer pane (Planilux)

Swisspacer V spacer bar with 3mm Polyurethane secondary seal

C Rating – Eco Classic/Contour

  • U VALUE 1.4
  • REHAU S706 / Edge PVCu frame system with full reinforcement
  • 4-20-4 Low E 0.04 uncorrected emissivity
  • Inner pane (Saint Gobain Planitherm Total)
  • 100% Air filled
  • Float outer pane (Planilux)

Aluminium spacer bar with 4.5mm Polyurethane secondary seal

C Rating – Vertical Sliding Windows

  • REHAU HERITAGE: PVCu frame system
  • 4-20-4 Low E 0.04 uncorrected emissivity
  • Inner pane (Saint Gobain Planitherm Total)
  • 90% Argon Gas, 10% Air filled
  • Low Iron outer pane (Saint Gobain Daimant)

Swiss spacer V spacer bar with 5.5mm Polyurethane secondary seal

Cristal Windows
Your Trusted Energy-Efficient Window & Door Supplier

Cristal Windows partners with Climatec to provide certified BFRC-rated windows. Under the BFRC rating scheme, Climatec (Reg No. 1363 M244) fabricates and supplies our window products, ensuring compliance with the latest energy efficiency standards.

For more information or to discuss your window upgrade, contact us today!

No Obligation – 100% Free

Industry Leading Accreditations

Cristal Windows is accredited by FENSA, Which? Trusted Trader, and other leading industry bodies, ensuring top-tier quality, safety, and reliability for every installation.

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Double Glazing Installation Coverage Areas

We offer expert installation of high-quality double & triple glazed windows, doors, bi-fold doors, patio doors, composite doors, conservatories, and roof lanterns. If your home is located outside of the areas we typically cover, feel free to give us a call—we’re happy to discuss availability and may still be able to arrange an installation in your area.

Cristal Windows: Local Double Glazing

When you choose Cristal Windows for your local double glazing installations, you are not only choosing an ethical, professional and family run business, but also a window company that provides high-quality products. We take the utmost care when installing our range of windows, doors, and conservatories and are accredited by trustworthy schemes such as FENSA.

We offer installations to homeowners in Berkshire, Hampshire, or Surrey.

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