Crittall-Style Windows Explained
“Crittall-style” has become shorthand for slim, black, grid-pattern steel windows and doors. The name comes from Crittall, the long-established steel window manufacturer, but the style is a category in its own right — a look defined by hot-rolled steel sections and very slim sightlines.
This guide explains where that distinctive look comes from, the difference between traditional and thermally broken sections, and what to consider before you specify.
Why steel windows have such slim sightlines
Steel is far stronger than aluminium or timber, so the frame can be much thinner while still carrying the glass. That is why a hot-rolled steel section can hold a large pane on a sightline of around 20mm, where other materials need a chunkier frame.
The result is more glass, more light and the crisp, gridded geometry people associate with the crittall-style look — equally at home on a Victorian villa or a contemporary extension.
Traditional vs thermally broken sections
Traditional W20-type sections give the slimmest, most authentic heritage sightlines and are ideal for conservation areas and like-for-like replacement.
Thermally broken W50 sections insert a polyamide break into the frame to cut heat loss and condensation, replicating the slim look while meeting modern energy expectations. If comfort and running costs matter, the thermally broken option is usually worth the slightly wider sightline.
Finishes, glazing and configurations
Steel windows and doors are finished in any RAL colour, so the classic matt black is just the starting point. Glazing ranges from single panes for heritage work to double or triple insulated units, with clear or reeded glass.
Beyond fixed and opening windows, the same sections make French and pivot doors, internal screens, room dividers and even shower screens — letting you carry one detail through a whole project.
Frequently asked
- Is 'crittall-style' the same as Crittall?
- No. Crittall is a specific manufacturer; 'crittall-style' describes the slim, gridded steel look that many makers, including us, produce.
- Are crittall-style windows energy efficient?
- Traditional sections prioritise the heritage look; for modern energy performance choose a thermally broken section with double or triple glazing.
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Tell us your sizes and target dates and our team will prepare a considered estimate. We survey, make and install across mainland UK.