Crittall Style Doors: A Comprehensive UK Homeowner's Guide

In the world of architectural glazing, few styles have captured the imagination and maintained their timeless appeal quite like Crittall style doors. Originating from a British company established in 1849, the distinctive aesthetic of slim, black steel frames with multiple glazing bars has become synonymous with industrial chic, elegant partitioning, and a sophisticated design statement. For UK homeowners considering an upgrade or new build, understanding what these doors entail, their benefits, and critical considerations is paramount.

What Are Crittall Style Doors?

Crittall style doors, often referred to as 'industrial style' or 'steel-framed' doors, are characterised by their distinctive grid-like appearance. While the original Crittall company still produces genuine steel-framed windows and doors, the term 'Crittall style' has broadened to encompass products that emulate this iconic look using various materials.

The hallmark features include:

• Slim Frames: Typically made from steel or aluminium, the frames are remarkably slender, maximising glass area.
• Grid Pattern: Multiple glazing bars (muntins and transoms) divide the glass into smaller, often rectangular, panes. This creates the signature grid aesthetic.
• Colour: Traditionally, they are powder-coated black, though other dark colours like anthracite grey are becoming popular.
• Material: Historically, they were always steel. Modern interpretations often use aluminium, which offers similar aesthetics with different performance characteristics.

These doors are versatile, used for internal partitions, external doors, bifold doors, sliding doors, and even shower screens, bringing a touch of industrial elegance to both contemporary and traditional properties.

Materials and Construction: Steel vs. Aluminium

When considering Crittall style doors, the primary material choice will be between genuine steel and aluminium. Each has distinct advantages and considerations for a UK home.

Steel Crittall Doors

• Authenticity: True to the original design, offering an unparalleled level of authenticity and heritage.
• Strength: Steel is incredibly strong, allowing for exceptionally thin sightlines and large panes of glass with minimal framing.
• Durability: Highly durable and long-lasting, especially when properly maintained and finished with modern powder coatings.
• Thermal Performance: Historically, steel was a poor insulator. However, modern steel frames incorporate thermal breaks to significantly improve U-values, making them suitable for external use.
• Weight: Steel is heavy, which can impact installation and require robust supporting structures.
• Cost: Generally the most expensive option due to material costs and specialised manufacturing processes.

Aluminium Crittall Style Doors

• Cost-Effectiveness: Typically more affordable than steel, making the style accessible to a wider range of budgets.
• Weight: Aluminium is lighter than steel, easing installation and reducing structural demands.
• Thermal Performance: Aluminium is an excellent conductor of heat, but modern systems incorporate sophisticated thermal breaks to achieve very good U-values, often matching or exceeding steel for external applications.
• Maintenance: Highly resistant to corrosion and requires minimal maintenance beyond cleaning.
• Design Flexibility: Can be extruded into various profiles, offering flexibility in design and often slightly thicker frames than true steel.
• Appearance: While excellent at mimicking the look, some discerning eyes might notice the slightly thicker profiles compared to genuine steel.

Benefits and Considerations for UK Homes

Potential Considerations:

• Cost: Crittall style doors, particularly genuine steel, represent a significant investment compared to standard UPVC or timber alternatives.
• Thermal Performance (External): While modern systems have improved dramatically, it's vital to ensure that external Crittall style doors meet current UK Building Regulations for thermal efficiency.
• Privacy: The extensive glazing offers little privacy unless obscured or frosted glass is used, which might detract from the classic aesthetic.
• Cleaning: The multiple small panes can mean more effort is required for cleaning compared to a single large pane of glass.
• Security: For external doors, ensure the chosen system incorporates multi-point locking mechanisms and toughened or laminated glass for enhanced security.

UK Building Regulations and Technical Specifications

For any external glazing installation in the UK, compliance with Building Regulations is not just recommended, but typically required. The key area for Crittall style doors is Part L (Conservation of Fuel and Power) and Part F (Ventilation).

Part L: Thermal Performance (England, 2022 Standards)

This regulation sets minimum standards for thermal efficiency, measured by the U-value (W/m²K), which indicates how well a material insulates. A lower U-value means better insulation.

• New Build Homes: Windows and doors must achieve a U-value of 1.2 W/m²K or better.
• Replacement Windows/Doors in Existing Homes: Must achieve a U-value of 1.4 W/m²K or better.

Modern Crittall style doors, whether steel or aluminium, use thermally broken frames and often incorporate double or even triple glazing to meet these stringent requirements. Always verify the U-value of the specific product you are considering.

Part F: Ventilation

If you are replacing existing windows and doors, Part F requires that the ventilation provision in the room is not made worse. This often means incorporating trickle vents into the new frames, even if the old ones didn't have them. Discuss this with your supplier, as trickle vents can sometimes impact the sleek aesthetic of Crittall style doors.

Other Relevant Regulations:

• Part K (Protection from Falling, Collision and Impact): Relates to safety glazing, requiring toughened or laminated glass in critical locations (e.g., within 800mm of floor level, or in and around doors).
• Part B (Fire Safety): For internal doors, particularly in multi-storey dwellings, fire ratings might be a consideration.
• Planning Permission: While often not required for internal alterations or like-for-like external replacements, always check with your local planning authority, especially if your property is listed or in a conservation area.

Technical Specifications Comparison:

Here's a general comparison of key technical aspects:

Feature	Genuine Steel Crittall Doors	Aluminium Crittall Style Doors
Frame Material	Solid Steel	Aluminium Alloy
Frame Sightlines	Extremely slim (e.g., 20-30mm)	Slim (e.g., 30-50mm), slightly thicker than steel
Thermal Break	Modern systems incorporate polyamide or similar	Standard feature in most external systems
Typical U-value (External)	1.2 - 1.6 W/m²K (with double glazing)	1.2 - 1.6 W/m²K (with double glazing)
Weight	Heavy	Medium
Corrosion Resistance	Excellent with modern galvanising & powder coating	Excellent, naturally resistant
Maintenance	Low (occasional cleaning, check seals)	Very Low (occasional cleaning)
Typical Cost	High	Medium to High

Choosing the Right Supplier and Installation

Selecting the right supplier and ensuring professional installation are crucial for the longevity and performance of your Crittall style doors.

• Experience: Choose a supplier with a proven track record in manufacturing and installing Crittall style systems, particularly for the material you choose (steel or aluminium).
• Accreditations: Look for accreditations such as FENSA or CERTASS for external glazing installations. These ensure compliance with Building Regulations and offer consumer protection.
• Warranty: A comprehensive warranty on both the product and installation provides peace of mind.
• Site Survey: A detailed site survey is essential to ensure accurate measurements and identify any potential structural challenges.
• Installation Expertise: The installation team should be experienced with the specific product, as correct fitting is vital for thermal performance, security, and smooth operation.
• Aftercare: Understand the aftercare and maintenance requirements for your chosen system.

Crittall style doors offer a powerful blend of historical charm and contemporary functionality, making them a desirable choice for many UK homeowners. By understanding the material differences, thermal performance, and regulatory requirements, you can make an informed decision that enhances your home's aesthetics and efficiency for years to come.

At Shard AG, we specialise in high-quality architectural glazing solutions for discerning UK homeowners. Our range of Crittall style doors, available in both authentic steel and advanced aluminium, is designed to meet the highest standards of aesthetics, performance, and Building Regulations compliance. We offer expert consultation, bespoke design, and professional installation to transform your home with timeless elegance and superior functionality. Contact us today to discuss your project and discover how we can bring your vision to life.