Updated U-values: Fully Certified and Future-Ready

At Bereco, we’re committed to transparency and performance that stands the test of time.

To ensure our products continue to meet evolving regulations, we’ve had their thermal performance independently reassessed and certified by the British Fenestration Rating Council (BFRC), a UKAS-accredited organisation. These updated figures reflect the latest industry standards and are aligned with the upcoming Future Homes Standard and Home Energy Model (HEM), which is set to replace SAP from 2027.

As one of the first timber window manufacturers in the UK to secure UKAS‑accredited, BFRC‑certified U‑values, Bereco continues to lead the way in verified thermal performance.

What’s new?

Our U-values are now certified using the latest methodology in accordance with BS EN ISO 10077-1:2017, ensuring full compliance with future regulatory requirements. Bereco products remain comfortably within current Building Regulations, with double-glazed U-values starting from 1.3 W/m²K, around 7% better than the requirements.

Why it matters

There is increasing focus on the accuracy and credibility of published U-values across the industry, and the upcoming Home Energy Model (HEM) is widely expected to require independently accredited U-values. By using independently verified figures from a recognised third party, we are helping our customers specify with confidence and future-proof their projects.

Accessing U-value reports

Our full range of BFRC-certified U-value reports is now available. You’ll find direct links included in your quotes and order confirmations, and they will shortly be available in our Resource Centre, making it easy to reference the data you need at every stage of your project.

Frequently Asked Questions

Why is it important that my U-value report is created by an accredited body?

U-values measure how energy efficient your windows and doors are, so it’s essential that this information is accurate. At Bereco, our U-value reports are created by the British Fenestration Rating Council (BFRC)—a UKAS-accredited organisation. This means the data meets current British Standards and is recognised by auditing bodies like FENSA.

What does it mean that the report follows BS EN ISO 10077-1:2017?

This is the British and European standard for calculating the thermal performance of windows and doors. If a report follows BS EN ISO 10077-1:2017, it means it’s based on precise simulation and calculation methods, ensuring the U-values are reliable, consistent, and regulation-compliant.

How can I tell if a U-value report is legitimate?

Look for the following key details:

• A report reference number and simulation number.
• UKAS accreditation clearly stated
• Confirmation that the report complies with BS EN ISO 10077-1:2017
• Issuer name, issue date, and product-specific information.

All Bereco reports include these details for full transparency and traceability.

How does having an official U-value report help meet future requirements under the Home Energy Model (HEM)?

The Home Energy Model (HEM) is set to replace the current SAP (Standard Assessment Procedure) and will be the new standard for calculating energy performance in homes. It places even greater emphasis on verified product data, especially U-values for windows and doors.

By using UKAS-accredited U-value reports, you can ensure your specifications are compliant with HEM’s data requirements. These reports provide auditable, third-party verified evidence that supports accurate modelling, helping you:

• Achieve compliance with Future Homes Standard targets
• Avoid delays in building control approval
• Gain smoother passage through planning and energy assessments

This means peace of mind that your project’s building fabric meets performance criteria, now and in the future.

Why have your U-values changed?

Our U-values were previously calculated using a different method. They’ve now been updated following independent assessment by a UKAS-accredited body, ensuring our products performance meet BS EN ISO 10077-1:2017.

Have your products changed?

No. There has been no change to the specification, design, or performance of our products. The updated values are based solely on a new calculation method and certification process.

Will the new U-values affect my existing quote or order?

No. Any quotes or orders issued before the update remain valid, and the U-values provided at the time still apply. The changes apply only to new quotes and documents issued from this point forward.

If you have any further questions, our team is happy to help, just get in touch