Crittall Style Doors: A Comprehensive UK Homeowner's Guide

In the world of architectural design, certain styles transcend fleeting trends to become timeless classics. Crittall style doors and windows are a prime example, offering a distinctive aesthetic that has graced homes and commercial buildings for over a century. Characterised by their slim, black steel frames and multiple glass panes, they evoke an industrial-chic elegance that is highly sought after in contemporary UK properties. But what exactly are Crittall style doors, and what should UK homeowners consider before investing in them?

What Are Crittall Style Doors?

The term 'Crittall' originates from Crittall Windows Ltd, a British company founded in 1849, which pioneered the manufacture of steel-framed windows and doors. While 'Crittall' is a brand name, it has become synonymous with the style itself, much like 'Hoover' for vacuum cleaners. Today, many manufacturers produce 'Crittall style' or 'industrial style' glazing, offering a similar aesthetic using various materials.

Key Characteristics:

• Slim Frames: The most defining feature is the exceptionally slender profile of the frames, typically made from steel, which maximises the glass area and allows for abundant natural light.
• Grid-like Panes: Multiple individual glass panes are separated by muntin bars, creating a distinctive grid pattern. This can range from large, symmetrical grids to more intricate designs.
• Dark Finish: Traditionally, Crittall style frames are finished in a matt black powder coating, contributing to their iconic industrial look. However, other colours are available.
• Durability: Genuine steel frames are incredibly robust and long-lasting.
• Versatility: Suitable for both internal and external applications, including doors, windows, room dividers, and shower screens.

Materials and Construction: Steel vs. Aluminium vs. uPVC

While the original Crittall doors are made from steel, the popularity of the style has led to manufacturers offering similar designs in other materials. Understanding the differences is crucial for making an informed decision for your UK home.

For external applications, the choice of material significantly impacts thermal performance, security, and longevity. Internal applications offer more flexibility, where aesthetics and room division are often the primary drivers.

UK Building Regulations and Technical Specifications

For any external door or window installation in the UK, compliance with Building Regulations is paramount. This ensures your home is safe, energy-efficient, and structurally sound. The most relevant parts for Crittall style doors are Part L (Conservation of Fuel and Power) and Part F (Ventilation).

Part L: Thermal Performance (U-Values)

This regulation dictates the maximum U-value (a measure of heat loss) for new and replacement windows and doors. The lower the U-value, the better the thermal insulation.

• New Build Windows/Doors: Maximum U-value of 1.2 W/m²K
• Replacement Windows/Doors: Maximum U-value of 1.4 W/m²K

Achieving these U-values with Crittall style doors, particularly steel, requires careful specification. Modern steel frames incorporate thermal breaks – non-conductive materials inserted into the frame profile to prevent heat transfer. Combined with high-performance double glazing (or sometimes triple glazing for very low U-values), these doors can meet current regulations.

Part F: Ventilation

New and replacement windows and doors must provide adequate ventilation. This typically means incorporating trickle vents or ensuring other means of ventilation are present in the room. Trickle vents are small, controllable openings that allow for continuous background ventilation, crucial for preventing condensation and maintaining indoor air quality.

Other Considerations:

• Glazing: For external doors, double glazing is standard. For internal doors, single glazing or laminated safety glass is common. Always ensure glass meets safety standards (e.g., BS EN 12150 for toughened glass).
• Security (Part Q): For external doors, security is vital. Look for multi-point locking systems, robust hinges, and toughened or laminated glass. Doors should be tested to PAS 24 standards.
• Weather Rating: External doors must be weather-tight, resisting wind and rain. Ask for performance ratings for air permeability, water tightness, and wind resistance.
• Fire Regulations (Part B): For internal applications, especially in multi-storey homes or certain layouts, fire-rated doors might be required. Steel frames can often be specified with fire-resistant glass to meet these requirements.

It is always advisable to consult with your local Building Control body or a qualified architect/surveyor to ensure your specific project complies with all relevant regulations.

Advantages and Disadvantages for UK Homeowners

Crittall style doors offer a compelling blend of aesthetics and functionality, but it's important to weigh both the pros and cons.

Advantages:

• Aesthetic Appeal: Unmistakable industrial-chic look that adds character and sophistication to any property, from period homes to modern new builds.
• Maximised Light: Slim frames allow for larger glass areas, flooding interiors with natural light and creating a sense of openness.
• Durability and Longevity: High-quality steel frames are incredibly robust, resistant to warping, and can last for decades with proper maintenance.
• Versatility: Suitable for a wide range of applications – external doors, internal room dividers, shower screens, conservatories, and more.
• Increased Property Value: Their timeless appeal and high-end finish can enhance the perceived value of your home.
• Space Creation: Internal Crittall style doors can delineate spaces without sacrificing light or a feeling of spaciousness, ideal for open-plan living.

Disadvantages:

• Cost: Genuine steel Crittall style doors are often a significant investment compared to standard uPVC or even some aluminium options.
• Thermal Performance (Historically): Older, un-thermally broken steel frames were poor insulators. Modern versions with thermal breaks perform well but require careful specification.
• Weight: Steel doors are heavy, requiring robust hinges and professional installation.
• Maintenance: While durable, steel frames may require occasional repainting or touch-ups to prevent corrosion, especially in coastal areas.
• Cleaning: The multiple small panes can mean more effort when it comes to cleaning the glass.
• Privacy: The extensive glazing offers limited privacy, which may be a concern for certain rooms unless obscured or smart glass is used.

Installation and Maintenance

Given the weight and precision required, professional installation is crucial for Crittall style doors, particularly for external applications. A reputable installer will ensure proper sealing, alignment, and compliance with all relevant Building Regulations.

Maintenance Tips:

• Regular Cleaning: Clean glass with a mild detergent and soft cloth. For frames, wipe down with a damp cloth to remove dirt and grime.
• Check Seals: Periodically inspect rubber seals around the glass and frame for any signs of perishing or damage, which can affect thermal performance and weather tightness.
• Lubricate Moving Parts: Hinges and locking mechanisms should be lubricated annually with a silicone-based spray to ensure smooth operation.
• Inspect Paintwork: For steel frames, check for any chips or scratches in the powder coating. Touch up promptly to prevent rust.
• Drainage: Ensure any drainage channels at the bottom of external doors are clear of debris.

Crittall Style Door Specification Comparison

Here's a comparison of typical specifications for external Crittall style doors made from different materials, focusing on meeting UK Building Regulations (Part L 2022).

Feature	Steel (Authentic Crittall Style)	Aluminium (Modern Crittall Style)	uPVC (Crittall Style Aesthetic)
Frame Material	Hot-rolled steel with thermal break	Thermally broken aluminium	Multi-chamber uPVC
Typical U-value (W/m²K)	1.2 - 1.4 (with double glazing)	1.2 - 1.4 (with double glazing)	1.2 - 1.4 (with double glazing)
Sightline (Frame Width)	20-30mm (internal bars), 40-60mm (outer frame)	30-50mm (internal bars), 60-80mm (outer frame)	50-70mm (internal bars), 80-100mm (outer frame)
Glazing Options	Double (toughened/laminated), Low-E coating, Argon gas	Double (toughened/laminated), Low-E coating, Argon gas	Double (toughened/laminated), Low-E coating, Argon gas
Security Features	Multi-point locking, robust hinges, PAS 24 compliant options	Multi-point locking, robust hinges, PAS 24 compliant options	Multi-point locking, robust hinges, PAS 24 compliant options
Durability	Excellent, highly resistant to impact and warping	Very good, corrosion-resistant	Good, resistant to rot and rust
Maintenance	Low (occasional touch-up for scratches)	Very Low	Very Low
Cost Range	High	Medium-High	Medium

Conclusion

Crittall style doors offer a distinctive and elegant solution for homeowners looking to add character, light, and a touch of industrial sophistication to their properties. Whether you opt for authentic steel, versatile aluminium, or a more budget-friendly uPVC interpretation, understanding the technical specifications and Building Regulations is key to making an informed choice.

By carefully considering the material, thermal performance, security features, and installation requirements, you can select Crittall style doors that not only enhance your home's aesthetic but also provide lasting performance and compliance with UK standards. Always engage with reputable suppliers and installers who can guide you through the options and ensure your new doors are a valuable, long-term asset to your home.

If you're considering Crittall style doors for your UK home, Shard AG specialises in high-quality architectural glazing solutions. Our expert team can provide detailed advice on material options, thermal performance, and compliance with the latest UK Building Regulations, helping you choose the perfect doors to complement your property's design and meet your specific requirements.