A++ Energy Standard Windows & Doors | Exceptional Performance

Exceptional Performance Without Compromise.

Exceeding Expectations in Energy Efficiency. At AT-ECO, we supply windows and doors that help homes and buildings achieve or exceed A++ energy ratings. Whether you're building a new home or upgrading for better energy performance, our product range supports long-term savings, better comfort, and regulatory compliance — all with striking aesthetics.

Modern Home with A++ Energy Rated Windows

What Is the A++ Energy Standard?

The A++ rating is part of the EU and UK energy labelling schemes, commonly used for windows, doors, and appliances. It signifies outstanding thermal efficiency, reducing heat loss and improving insulation.

To achieve an A++ rating, a product must meet very low U-values, typically below:

Windows: ≤ 0.8 W/m²K
Doors: ≤ 1.0 W/m²K

A++ products support:

Lower heating bills
Improved thermal comfort
Strong alignment with Part L regulations and future energy targets

Benefits of A++ Rated Windows and Doors

Energy Cost Savings: Reduced heat loss in winter and overheating in summer
Enhanced Insulation: Triple glazing and multi-chamber frames ensure low U-values
Modern Aesthetics: Slim profiles, flush finishes, and custom design options
Increased Property Value: Better EPC rating improves resale potential
Climate Responsibility: Lower energy consumption = lower carbon emissions

High-Performance Products for A++ Homes

Internorm

KF310 – Compact uPVC-Aluminium profile, strong thermal values
KV350 – Integrated blind system, energy-saving and glare control in one
KF510 – Slim sash, uPVC-Aluminium with I-tec Secure and triple glazing
KF520 – Frameless full-glass sash for contemporary Passive-level performance

Drutex

IGLO 5 – Five-chamber uPVC profile, budget-friendly with great insulation
IDEAL NEO – Flush-frame, minimalist design with high thermal specs
DUOLINE – Timber-Aluminium system offering natural finish with excellent U-values
MB-86N / MB-79N SI – Aluminium systems tailored for low-energy and A++ installations

Reynaers

ML8 – Insulated aluminium for low-energy builds and refurbishments
SL38 – Slimline profile with strong performance and modern appearance
CS77 – Versatile system, highly insulating and PAS 24 compatible

Schüco

Premium aluminium systems designed for airtightness, low U-values, and long-lasting aesthetics

A++ Product Comparison Table

Product	U-Value (W/m²K)	Frame Material	Glazing	Special Features
Internorm KF520	~0.63	uPVC-Aluminium	Triple	Frameless design, I-tec Secure
Internorm KV350	~0.79	uPVC-Aluminium	Triple	Integrated blinds
Drutex DUOLINE	~0.79-0.90	Timber-Aluminium	Triple	Timber look, alu exterior
Reynaers CS77	~0.95	Aluminium	Triple	High insulation, Secure design

When Should You Choose A++ Standard?

New builds aiming for EPC A or Passive-level performance
Upgrades where space or budget limits full Passive House spec
Projects requiring strong insulation, slim design, or concealed shading
Clients prioritising both performance and architectural design

Planning for A++ Performance

Define your insulation and energy goals
Specify window/door U-values in your building plan
Model your home with SAP or PHPP tools
Choose A++ certified glazing and frames early in the project
Ensure installation is airtight and detail-free for thermal bridging

Glossary of Key Terms

U-Value – Measures heat transfer; lower = better insulation
EPC – Energy Performance Certificate (UK requirement)
Part L – UK Building Regulations focused on fuel conservation
Triple Glazing – Three panes of glass for insulation and noise control
I-tec – Internorm technology for glazing, insulation, and shading

Why Choose AT-ECO?

Decades of experience specifying A-rated window systems
FENSA-certified installers for secure, regulation-compliant fit
Products from Internorm, Drutex, Reynaers, and Schüco — trusted across Europe
Clear, honest performance data to help you meet energy standards with confidence

Resources and Further Reading

Recent Work

Working closely with architects, builders, and homeowners, we’ve delivered systems that combine thermal efficiency, modern aesthetics, and long-term durability—across private residences, sustainable developments, and architect-led designs.

Swanton House: Modern Renovation in Kent

The renovation project was successfully completed on schedule, surpassing initial insulation and energy efficiency goals by an impressive 70% and delivering a sleek, contemporary finish.

A++ Energy Standard | Windows & Doors for Exceptional Performance