The “Crittall look”, characterised by slim black frames, multiple horizontal glazing bars, and an industrial, Art Deco-inspired aesthetic, has become the gold standard for high-end UK renovations. Whether used as external French doors for a kitchen extension or as internal glass partitions to “zone” an open-plan living space, the demand for this look in Windsor, Berkshire, and across London is at an all-time high.
However, many homeowners face a critical decision: should they invest in original steel or opt for modern aluminium heritage systems?
While steel was the pioneer of this design, advancements in glazing technology mean that aluminium is now the preferred choice for the majority of residential projects. At Inspired Glazing, we specialise in the survey and installation of high-performance aluminium systems that replicate the steel aesthetic without the traditional drawbacks.
This guide compares both materials across five key metrics: thermal performance, maintenance, security, versatility, and cost.
1. Thermal Performance: The Cold Truth About Steel
One of the primary concerns for any homeowner in the UK is energy efficiency. With the 2026 Future Homes Standard approaching, the focus on reducing heat loss has never been greater.
Steel is a naturally conductive material. Historically, steel frames were notorious for “cold bridging,” leading to excessive heat loss and significant condensation issues on the interior of the frame. While modern high-end steel systems are available with thermal breaks, they often require expensive triple glazing to reach the same efficiency levels that a standard aluminium system achieves with double glazing.
Aluminium Heritage Systems, such as those we install, are designed with a polyamide thermal break. This is a highly insulating material that separates the inner and outer parts of the frame, effectively stopping heat transfer.
- Typical U-Values: Aluminium heritage doors often achieve U-values of around 1.4 W/m²K using standard double glazing.
- Energy Ratings: Most of our systems are B-rated or higher, ensuring your home remains warm in winter and cool in summer.
For property developers and homeowners in Windsor and London, choosing aluminium means a more comfortable living environment and lower energy bills compared to non-thermally broken steel alternatives.
2. Maintenance and Durability: Aluminium Wins Long-Term
In the damp UK climate, the longevity of your window and door frames is a vital consideration.
Steel Maintenance
Steel is incredibly strong, but it is susceptible to corrosion. Even with modern galvanised coatings, steel frames can rust if the surface is scratched or if they are installed in coastal or high-pollution urban areas. This necessitates periodic repainting and specialist rust treatment to prevent structural degradation.
Aluminium Durability
Aluminium is naturally resistant to rust and rot. Our heritage doors are finished with a marine-grade powder coating, which is baked onto the metal.
- Longevity: An aluminium frame can easily last 40+ years with minimal upkeep.
- Upkeep: Maintenance is limited to an occasional wipe-down with soapy water to remove dust and grit.
- Weather-tight sealing: Our precise fit installations ensure that the weather-stripping remains effective, preventing draughts and water ingress for decades.
For more information on the benefits of aluminium, see our detailed guide on Aluminium vs. uPVC.
3. Aesthetic Authenticity: Sightlines and Style
The main draw of the “Crittall” style is the ultra-slim sightline. Steel is approximately three times stronger than aluminium, which historically allowed for the thinnest possible frames.
However, modern engineering has closed this gap. The Heritage and Steel-Look aluminium systems we provide feature incredibly slim profiles.
- Mullions and Transoms: Frames can be as slim as 34mm.
- Astragal Bars: We use applied glazing bars to replicate the “multi-pane” look of original steel windows with millimetre precision.
When viewed from a standard distance, the visual difference between a high-quality aluminium heritage door and a genuine steel one is negligible. For homeowners looking to maintain the character of a Victorian or Edwardian property in Berkshire, aluminium offers the perfect balance of “period” aesthetics and modern performance.
4. Internal Versatility: The Korniche Revolution
“Crittall-style” isn’t just for external doors. One of the biggest trends in London property renovation is the use of internal glass partitions. These allow light to flow through a home while providing acoustic privacy, perfect for home offices or separating a kitchen from a formal dining room.
We are proud to offer the Korniche Glass Partition System. This aluminium internal system is a game-changer for interior design:
- SpeedBead Technology: Allows for a faster, cleaner installation with no visible beads.
- Modular Design: Can be configured as single doors, French doors, or fixed glass walls up to 3 metres high.
- Acoustic Options: Can be fitted with 6.8mm acoustic laminate glass to significantly reduce noise transfer between rooms.
Whether you are looking for a sleek room divider or a secure home office entrance, the Korniche system provides a premium industrial look that is far lighter and easier to install than steel.
5. Cost and Value Comparison
Cost is often the deciding factor for our clients. Because aluminium is easier to fabricate and the raw material is more readily available than high-grade architectural steel, the price difference is substantial.
In many cases, genuine steel can be 3 to 4 times the price of a high-performance aluminium heritage system. By choosing aluminium, you can achieve the exact same aesthetic while redirecting your budget toward other areas of your renovation.
Case Study: Kitchen Extension in Windsor
Challenge: A homeowner in Windsor wanted to replace an old set of uPVC bifolds with a more “industrial” look to match their new kitchen extension. They were concerned that steel would be too heavy for their daily use and too expensive for the overall project budget.
Solution: Inspired Glazing surveyed the site and recommended a set of Aluminium Heritage French Doors with matching side panels. We used a 34mm slimline frame and applied horizontal bars to mimic the steel look.
Result: The installation provided a “precise fit” that dramatically increased the natural light in the kitchen. The homeowner achieved the exact aesthetic they wanted at a fraction of the cost of steel, with the added benefit of modern multi-point locking systems for enhanced security.
Why Choose Inspired Glazing for Your Heritage Project?
Choosing the right material is only half the battle; the quality of the installation is what ensures long-term performance. At Inspired Glazing, we provide a comprehensive service across Windsor, Berkshire, and all 32 London boroughs.
- Made-to-Measure: Every door is manufactured to the exact millimetre of your opening.
- Technical Precision: From the initial survey to the final weather-tight sealing, we focus on “clean workmanship.”
- Local Expertise: We understand the specific architectural requirements of London and Berkshire homes.
If you are looking for Aluminium Windows near you or want to upgrade your home with the iconic heritage look, our team is ready to help.
Frequently Asked Questions
Q: Can I use aluminium heritage doors for my external balcony?
A: Yes. Our aluminium heritage systems are fully weather-rated and feature high-security locking, making them ideal for both ground floor extensions and upper-floor balconies.
Q: Do aluminium heritage doors come in colours other than black?
A: While RAL 9005 (Black) is the most popular for the Crittall look, we can provide frames in any RAL colour, including Anthracite Grey or White, to suit your property’s style.
Q: Are internal partitions as secure as external doors?
A: Our internal systems, like the Korniche partition, feature discreet magnetic locking and robust handles. While not designed for external security, they are incredibly sturdy and durable for daily internal use.
Request a Quotation Today
Ready to transform your home with the classic look of steel and the modern performance of aluminium? Contact Inspired Glazing for a clear, no-obligation quotation.
Call us: 01753 965 005
Visit our website: www.inspiredglazing.co.uk
We serve Windsor, Berkshire, and the surrounding 50-mile radius, including all London boroughs.