What Are Crittall Windows?

 

Crittall is a British manufacturer of steel windows and doors rather than the generic name for every slim black-framed window.

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Genuine Crittall windows are manufactured using steel profiles and are made to suit the dimensions and design of the individual project.

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The company produces external windows, external doors, internal glazed doors, sliding doors, screens and fire-rated internal systems.

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The familiar appearance normally includes:

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• Slender steel frames

• Large areas of glass

• Strong horizontal and vertical glazing bars

• Side-hung opening windows

• Black or dark-coloured finishes

• Matching glazed doors and screens

• Industrial or Art Deco styling

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Although black is the best-known finish, genuine steel windows and doors can be supplied in a much wider range of colours.

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Genuine Crittall Versus Crittall-Style Windows

 

The terms are often used interchangeably, but they do not describe exactly the same product.

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Genuine Crittall windows and doors are manufactured by Crittall Windows using its own steel systems.

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Crittall-style windows and doors reproduce the slim, grid-framed appearance but may be manufactured by another steel-window company or made from aluminium, timber or uPVC.

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Alternatives may provide a similar visual effect, but there can be significant differences in:

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• Frame material

• Profile thickness

• Corner construction

• Glazing-bar design

• Opening mechanisms

• Thermal performance

• Security

• Durability

• Price

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A quotation describing a product as “Crittall style” should not be assumed to include genuine Crittall frames.

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Ask the installer to identify the manufacturer, frame system and material being proposed.

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Why Are Crittall-Style Windows Popular?

 

Slim-framed windows and doors allow a high proportion of glass within the overall opening. This can bring more daylight into a room and create clearer views than many heavier frame systems.

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Their strong geometric design can complement:

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• Victorian and Edwardian homes

• Art Deco properties

• Converted factories and warehouses

• Contemporary extensions

• Open-plan kitchens

• Home offices

• Entrance halls

• Garden rooms

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Steel is particularly well suited to slender frames because of its strength. The narrow profiles can support substantial glazed sections without creating the bulky appearance associated with some alternative materials.

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Crittall-Style Windows

 

Crittall-style windows can be produced in several materials.

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Steel Windows

Steel provides the most authentic appearance and is the material used for genuine Crittall windows.

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Benefits can include:

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• Very slender sightlines

• Strong frames

• Bespoke sizes and configurations

• Traditional steel-window character

• Suitable heritage profiles

• Long service life

• Wide choice of powder-coated colours

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Modern steel frames can be galvanised and factory finished to protect them from corrosion and reduce maintenance.

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Aluminium Windows

Aluminium is widely used to create steel-look windows and doors.

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It can provide relatively slim frames, modern double glazing and a broad choice of powder-coated colours. Aluminium alternatives are often more readily available and may cost less than bespoke steel.

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However, the profiles and glazing bars are generally different from genuine steel windows. Homeowners should inspect samples rather than relying only on photographs.

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uPVC Windows

Some manufacturers offer uPVC windows with dark frames and applied glazing bars intended to suggest a Crittall-style appearance.

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These can provide an affordable and low-maintenance solution, but uPVC frames are normally wider than steel or aluminium. They are therefore unlikely to recreate the same slender proportions.

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uPVC may be suitable where the homeowner wants a general black-grid appearance rather than an authentic steel-window design.

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Double Glazed Crittall Windows

 

Older steel windows were commonly fitted with single glass and can be associated with draughts, condensation and heat loss.

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Modern double glazed Crittall windows combine slender steel frames with insulated glazing units. Current systems can incorporate features such as low-emissivity glass, insulating gas and warm-edge spacer bars while preserving slim frame proportions.

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A double glazed unit contains two panes of glass separated by a sealed cavity. The specification may include:

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• Low-E energy-efficient glass

• Argon or another insulating gas

• Warm-edge spacer bars

• Toughened safety glass

• Laminated security glass

• Acoustic glazing

• Solar-control glass

• Obscure or patterned glass

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The thickness of the glazing unit must be compatible with the chosen steel profile. Different systems can accommodate different glass depths, so the frame and glass should be specified together.

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Crittall Double Glazing and Energy Efficiency

 

The energy performance of a steel window depends on more than the number of glass panes.

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Important factors include:

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• Whether the frame is thermally enhanced

• The whole-window U-value

• Glass coatings

• Gas-filled glazing cavities

• Spacer-bar construction

• Weather seals

• Frame junctions

• Installation quality

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Modern thermally enhanced steel systems are available for projects where energy efficiency must be balanced with slim sightlines. Crittall currently offers thermally enhanced external window and door options alongside its traditional steel systems.

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Ask the supplier for the performance of the complete window or door rather than relying only on the centre-pane U-value of the glass.

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Replacing Original Steel Windows

 

Original steel windows may be an important part of the character of a period property.

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Before replacing them, consider whether they could be:

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• Professionally repaired

• Realigned

• Draught-proofed

• Reglazed

• Stripped and refinished

• Upgraded with secondary glazing

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Where replacement is necessary, a specialist steel system may reproduce the original frame dimensions and glazing pattern more accurately than standard uPVC or aluminium windows.

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The Steel Window Association notes that modern steel systems can provide improved glazing, security and thermal performance while retaining the slender appearance associated with traditional steel windows.

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Crittall Windows and Doors

 

Matching steel windows and doors can create a consistent appearance across an extension or entire property.

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External options can include:

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• Single glazed doors

• Double doors

• French doors

• Sliding doors

• Fixed side screens

• Fanlights

• Steel-framed entrance doors

• Large garden openings

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Genuine Crittall external doors are made to measure and can be produced using the same characteristic steel profiles as the company’s window systems.

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The final configuration should consider ventilation, access, security, threshold design and the amount of clear opening required.

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Crittall Internal Doors

 

Crittall internal doors are used to separate rooms while allowing light and views to pass between them.

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They are particularly popular between:

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• Kitchens and dining rooms

• Living rooms and hallways

• Home offices and open-plan spaces

• Bedrooms and dressing rooms

• Entrance halls and reception rooms

• Pantries and utility areas

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Available arrangements can include hinged single doors, double doors, sliding doors, pocket doors and fixed glazed screens. Genuine Crittall internal doors can be customised through the frame layout, colour, glazing and hardware.

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Internal steel doors can make a room feel divided without creating the enclosed effect of a solid wall or timber door.

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Internal Sliding Doors

 

Sliding Crittall-style doors can be useful where there is insufficient space for a hinged door to swing open.

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They may be:

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• Surface mounted

• Suspended from a track

• Designed as pocket doors

• Combined with fixed side screens

• Installed as paired sliding panels

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Sliding doors are particularly useful for separating kitchens, dining areas and home offices.

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The design should allow suitable space for the panel to slide and provide access for future maintenance of the track and rollers.

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Black Crittall Doors

 

Black remains the most popular colour for Crittall and steel-style doors.

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Black frames emphasise the glazing-grid pattern and can complement:

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• White or neutral walls

• Exposed brickwork

• Timber flooring

• Industrial interiors

• Contemporary kitchens

• Traditional entrance halls

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However, black is not the only option. Steel frames can be powder coated in grey, white, green and many other colours.

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Genuine Crittall internal products are available in black, several standard colours and wider RAL colour choices.

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A softer grey, cream or bronze finish may integrate more comfortably with some traditional interiors.

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Glazing Options for Internal Doors

 

Clear glass allows the greatest amount of light to pass between rooms, but other options may provide more privacy or decoration.

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Choices can include:

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• Clear glass

• Frosted glass

• Reeded glass

• Fluted glass

• Smoked glass

• Tinted glass

• Laminated glass

• Acoustic glass

• Fire-resistant glass

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Reeded or frosted glass can work well in home offices, bathrooms and utility rooms where some privacy is required.

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Safety glass should be used where required, particularly in doors and glazing close to floor level.

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Fire-Rated Internal Doors

 

A standard glazed internal door must not be assumed to provide fire resistance.

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Where the position of the door requires a fire rating, the complete doorset must be designed, manufactured and tested for that purpose.

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This includes the frame, glass, hinges, seals, ironmongery and method of installation.

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Crittall produces a dedicated fire-rated internal door and screen system for locations requiring tested fire protection.

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This can be important where glazed doors are proposed between:

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• A garage and the house

• A protected hallway and another room

• Different areas of a converted building

• Commercial spaces

• Rooms forming part of a protected escape route

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Building Regulations advice should be obtained before replacing an existing fire door with a glazed alternative.

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Security for External Windows and Doors

 

External Crittall windows and doors should be specified differently from purely internal screens.

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Security considerations may include:

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• Multi-point locking

• Lockable handles

• Laminated security glass

• Secure hinges

• Reinforced locking points

• Internal glazing

• Tested door and window systems

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Ground-floor windows, entrance doors and easily accessible garden doors may require an enhanced security specification.

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Ask whether the exact product being quoted has been tested to a recognised security standard.

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Crittall-Style Doors in Extensions

 

Steel-framed doors are frequently used in rear extensions because their slim profiles can create a strong connection between the interior and garden.

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They work particularly well with:

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• Brick extensions

• Industrial-style interiors

• Exposed steelwork

• Pitched glazed roofs

• Contemporary kitchens

• Traditional London houses

• Courtyard gardens

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The grid pattern should be designed around the proportions of the opening. Too many glazing bars can make a small elevation feel busy, while too few may lose the distinctive steel-frame appearance.

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Listed Buildings and Conservation Areas

 

Original steel windows may contribute to the architectural character of a listed building or conservation-area property.

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Planning permission or listed building consent may be required before they are replaced or materially altered.

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The local authority may ask for:

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• Photographs of the existing windows

• Existing and proposed elevations

• Detailed frame sections

• Glazing-bar dimensions

• Material and colour information

• A window-condition report

• Justification for replacement

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Using a product described as Crittall-style does not automatically make it acceptable for a protected building. The proposed profiles, glass and opening arrangement should be compared carefully with the original windows.

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Maintenance

 

Modern steel windows and doors generally require less maintenance than neglected historic steel frames, particularly where the frames have been galvanised and factory coated.

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Routine care may include:

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• Cleaning frames with a mild solution

• Keeping drainage channels clear

• Checking external seals

• Lubricating locks and hinges

• Inspecting glass and glazing beads

• Repairing damage to the coating

• Adjusting doors that become misaligned

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Genuine Crittall products use galvanised and powder-coated steel to improve resistance to corrosion and provide a durable finish.

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Damage to the protective coating should be repaired promptly, particularly on external frames.

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Crittall Window and Door Costs

 

The cost of Crittall windows and doors depends on:

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• Genuine Crittall or another manufacturer

• Steel, aluminium or uPVC construction

• Size of the opening

• Number of frame sections

• Internal or external use

• Double-glazing specification

• Door configuration

• Frame colour

• Hardware

• Structural alterations

• Access and installation requirements

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Bespoke steel frames will normally cost more than mass-produced uPVC alternatives. Aluminium steel-look systems may offer a middle option, depending on the product and installation.

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Internal glazed screens can also vary considerably in price depending on whether they are fixed, hinged, sliding or fire rated.

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When comparing quotations, confirm whether they include:

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• Survey and design

• Frames and glass

• Handles and locking systems

• Delivery

• Installation

• Structural supports

• Internal and external finishing

• Waste removal

• Certification

• Guarantees

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Choosing an Installer

 

Installing slim steel windows and doors requires accurate surveying and careful alignment.

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Before appointing a supplier, ask:

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• Is this genuine Crittall or a Crittall-style system?

• Who manufactures the frames?

• Are the frames steel, aluminium or uPVC?

• What is the whole-window U-value?

• What glass is included?

• Is the external door security tested?

• Is any required fire rating certified?

• Who will carry out the installation?

• What guarantees are provided?

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Viewing a completed installation and a full-size frame sample can help you compare the true sightlines, finish and build quality.

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Find Trusted Crittall-Style Window and Door Installers

 

The quality of the frame, glass and installation all affect the appearance and performance of steel and steel-look glazing.

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APN Double Glazing can connect homeowners with experienced local installers who can explain the differences between genuine Crittall, steel, aluminium and uPVC alternatives.

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Get in touch for expert advice and a free, no-obligation quote.