Crittall Style Doors: A Comprehensive UK Homeowner's Guide

Crittall style doors and screens have experienced a remarkable resurgence in popularity across the UK, becoming a defining feature in both period properties and contemporary new builds. Their distinctive aesthetic, characterised by slender steel frames and multiple glass panes, offers a unique blend of industrial charm and elegant sophistication. But beyond their undeniable visual appeal, what exactly are Crittall style doors, and what practical considerations should UK homeowners be aware of before investing?

This comprehensive guide will delve into the world of Crittall style glazing, explaining their history, technical specifications, benefits, potential drawbacks, and crucial compliance with UK Building Regulations. Our aim is to provide you with the expert insights needed to make an informed decision for your home.

What Are Crittall Style Doors?

The term 'Crittall' originally refers to Crittall Windows Ltd, a British company founded in 1849, renowned for pioneering the manufacture of steel-framed windows and doors. Their iconic designs, featuring slim profiles and grid-like glazing bars, became synonymous with the Art Deco and Modernist architectural movements of the early 20th century. Today, 'Crittall style' has become a generic term used to describe any glazing system that emulates this distinctive aesthetic, whether made from steel, aluminium, or even timber.

These doors and screens are typically characterised by:

• Slim Profiles: Exceptionally thin frames and glazing bars maximise natural light and create a minimalist, elegant look.
• Grid Pattern: Multiple individual glass panes separated by horizontal and vertical glazing bars, forming a characteristic grid.
• Materiality: Traditionally made from steel, modern interpretations often use aluminium for its lighter weight, corrosion resistance, and thermal performance.
• Finish: Most commonly seen in matt black, but other colours are available to suit various interior and exterior schemes.

Steel vs. Aluminium Crittall Style

While original Crittall products are made from hot-rolled steel, many modern alternatives utilise aluminium. Understanding the differences is key:

Feature	Steel Crittall Style	Aluminium Crittall Style
Material Strength	Extremely high, allowing for the slimmest profiles.	High, but typically slightly thicker profiles than steel for equivalent strength.
Durability & Longevity	Exceptional, with proper maintenance (rust prevention).	Very good, naturally corrosion-resistant.
Thermal Performance (U-value)	Historically challenging; modern systems use thermal breaks but can still be lower than aluminium.	Generally better thermal performance due to inherent thermal break capabilities. Easier to achieve lower U-values.
Weight	Heavier, requiring robust structural support.	Lighter, easier to handle and install.
Cost	Generally higher due to material and manufacturing complexity.	Often more cost-effective.
Maintenance	May require more attention to prevent rust, especially externally.	Low maintenance, resistant to corrosion.
Aesthetics	Authentic, industrial feel; ultra-slim sightlines.	Very close resemblance; slightly thicker profiles may be noticeable to a keen eye.

Benefits of Crittall Style Doors and Screens

The enduring popularity of Crittall style glazing is no accident. They offer a multitude of advantages for UK homeowners:

Technical Considerations and UK Building Regulations

Installing Crittall style doors, especially in external applications or as part of an extension, requires careful consideration of UK Building Regulations. Compliance is not optional and ensures your home is safe, energy-efficient, and structurally sound.

Thermal Performance (Part L)

One of the most critical aspects for external doors and windows is thermal performance, governed by Part L (Conservation of Fuel and Power) of the Building Regulations. This is measured by the U-value, which indicates how effectively a material insulates. A lower U-value means better insulation.

• New Builds & Extensions: For new dwelling builds and extensions, external windows and doors must achieve a U-value of 1.2 W/m²K or better.
• Replacement Windows & Doors: For existing dwellings, replacement external windows and doors must achieve a U-value of 1.4 W/m²K or better.

Achieving these U-values with slim-profile Crittall style doors requires advanced glazing technology, such as double or even triple glazing, and thermally broken frames. A thermal break is a non-conductive material inserted into the frame to prevent heat transfer between the inner and outer sections. Without effective thermal breaks, slim steel frames can be significant thermal bridges, leading to heat loss and condensation.

Safety Glazing (Part K)

Part K (Protection from Falling, Collision and Impact) dictates that glazing in critical locations must be safety glass (toughened or laminated) to prevent injury in case of breakage. Critical locations include:

• Glazing in doors or within 300mm of a door edge.
• Glazing below 800mm from floor level in windows.

Given the grid-like nature of Crittall style doors, virtually all panes will fall into a critical location and therefore must be safety glass. This is a non-negotiable requirement for all reputable manufacturers.

Ventilation (Part F)

Part F (Ventilation) ensures adequate fresh air provision. If you are replacing existing windows or doors, or installing new ones as part of an extension, you must ensure that the ventilation strategy for the room or dwelling is maintained or improved. This often means incorporating trickle vents into the frames, even if they are very slim. Discuss ventilation requirements with your supplier and Building Control.

Structural Considerations

Especially for large Crittall style screens or doors, the weight, particularly of steel systems, needs to be considered. Ensure your existing structure or new opening can adequately support the load. This may require consultation with a structural engineer.

Fire Safety (Part B)

While less common for standard residential installations, if Crittall style doors are part of a fire-rated partition or exit route in a multi-occupancy building or certain commercial settings, they would need to comply with Part B (Fire Safety). This would require specialist fire-rated glazing and frame systems.

Installation and Maintenance

Proper installation is paramount to the performance and longevity of Crittall style doors. Due to their precision engineering and often significant weight, professional installation by experienced fitters is highly recommended. Incorrect installation can lead to issues with thermal performance, security, and operation.

Maintenance:

• Cleaning: Regular cleaning of glass and frames with mild soap and water is usually sufficient. Avoid abrasive cleaners.
• Moving Parts: Hinges and locking mechanisms should be checked periodically and lubricated as per the manufacturer's instructions to ensure smooth operation.
• Steel Frames: For external steel frames, inspect for any signs of rust or paint damage, and address them promptly to prevent corrosion. Modern steel systems often come with durable powder coatings that require less maintenance.

Cost Implications

Crittall style doors and screens are generally considered a premium product. The cost can vary significantly based on:

• Material: Steel systems are typically more expensive than aluminium.
• Size & Complexity: Larger units, those with more panes, or bespoke designs will incur higher costs.
• Glazing Type: Double or triple glazing, specialist safety glass, or acoustic glass will add to the price.
• Thermal Performance: Systems designed to meet stringent U-value requirements often involve more advanced manufacturing and materials.
• Installation: Professional installation is an additional, but essential, cost.

While the initial outlay might be higher than standard UPVC or timber alternatives, the durability, longevity, and timeless aesthetic of Crittall style glazing often represent a worthwhile long-term investment in your home's value and appeal.

Choosing the Right Supplier

When considering Crittall style doors for your UK home, selecting a reputable supplier is crucial. Look for companies with a proven track record, who can demonstrate:

• Expertise: In-depth knowledge of both steel and aluminium systems.
• Compliance: A clear understanding of and adherence to UK Building Regulations (Part L, K, F etc.).
• Quality: High-quality materials and manufacturing processes.
• Accreditation: Membership of industry bodies like FENSA or CERTASS for external glazing installations.
• Warranty: Comprehensive guarantees on both products and installation.

At Shard AG, we specialise in high-performance architectural glazing solutions, including bespoke Crittall style doors and screens. Our expert team works closely with UK homeowners, architects, and builders to design, supply, and install systems that not only meet stringent Building Regulations but also exceed aesthetic and performance expectations. We offer a range of thermally broken steel and aluminium options, ensuring you achieve the perfect balance of style, efficiency, and compliance for your project.