Steel Door Online

Steel doors in a refined interior

Our Story

How Steel Doors Online began

Built from real UK projects — where customers needed better guidance on sightlines, glazing, performance, and FD30 fire compliance.

From bespoke joinery to specialist steel systems

Colin’s Sash Windows was established in 2014 with a focus on bespoke, made to measure products rather than off the shelf solutions. Over time, our customers began requesting more internal steel doors, particularly for open plan layouts, extensions, and high specification refurbishments.

Later, double glazed external steel doors started to be requested to match the internal doors. We’ve chosen the system specified in the Battersea Power Station refurbishment. As demand grew, so did the complexity — and customers needed clearer answers before ordering.

2014

Colin’s Sash Windows established

A UK business built around bespoke, made to measure products — prioritising correct design, measurements, and long term performance.

Growing demand

Internal steel doors became a core request

Particularly for open plan layouts, extensions, and high specification refurbishments where sightlines and glazing bar layouts matter.

Next step

External steel doors followed

Customers wanted matching external systems — including double glazed solutions — aligned to premium refurbishment standards.

The challenge

More performance questions, less clear information

Advice was needed on acoustic performance, glazing choices, and increasingly, FD30 fire rated steel doors for kitchens, stairwells and escape routes. Many customers struggled to find reliable information online about what was genuinely fire rated and what was not.

Why Steel Doors Online exists

Steel Doors Online was created as a dedicated platform to address this gap. By separating our steel door offering from our wider window and door business, we’re able to focus entirely on education, technical accuracy, and compliance. This includes helping customers understand when FD30 fire rated steel doors are required, how they should be specified, and what limitations apply to glass, frame construction, and installation.

Behind Steel Doors Online is the same team, supply chain, and product knowledge that has supported thousands of UK projects through Colin’s Sash Windows. The difference is specialisation. Steel doors — particularly fire rated steel doors — demand careful specification and experienced oversight. This site exists to ensure they are supplied correctly, first time.

Need guidance before you specify? We’ll help you confirm sightlines, glazing options, and FD30 requirements before your order goes into production.
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01525 552131

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