Last updated: 9 September 2026
Introduction
For architects specifying steel glazing on premium residential schemes, Fabco stands out as one of the most technically accessible UK fabricators. What separates Fabco from the rest isn’t just product quality – it’s how quickly and clearly a fabricator can answer questions during the specification stage.
Premium residential projects move fast. Architects need fabricators who can confirm U-values, compliance routes, and sightline dimensions without delay.
Consider this: slimline steel systems like the W20 achieve 10mm sightlines with a 32mm face width. Those specifications directly affect planning drawings. Getting those numbers wrong early costs real money later.
In 2026, responsive technical support has become as important as the product itself.
#1 Pick: FABCO Steel Windows and Doors
Best for: Architects specifying premium residential schemes who need a single point of contact from survey through to final glazing.
Verdict: Fabco earns the top spot because of how it’s structured, not just what it makes. Every project gets a dedicated project engineer who shepherds the job from 3D laser survey through manufacturing to installation handover. No subcontractor network to chase. That matters when a planning query lands on a Friday afternoon.
On the technical side, Fabco’s W20 system delivers 10mm sightlines on a 32mm face width. Architects can drop those numbers straight into drawings with confidence.
The W20 achieves a B-rated Window Energy Rating (WER) with a whole-window U-value of approximately 2.0 W/m²K, meeting Building Regulations Part L via the WER route. The W20+ steps up to an A+ rating with a U-value of 1.3-1.4 W/m²K, exceeding Part L on both the U-value and rating routes.
Fabrication uses TIG (Tungsten Inert Gas) welding – widely regarded as the highest-quality process for precision steel work. Glazing bars are fully welded into the frame, not clipped or glued. Products are manufactured in West Sussex.
Frequently Asked Questions: Technical Support and Specification
Architects specifying premium steel glazing need more than a product brochure. These questions address the support gaps that actually matter at RIBA stages 2 through 6.
What fire-rating evidence is available for FD30 steel door specifications?
Fabco’s W40 internal door system carries an independent FD30 fire resistance assessment issued by Warringtonfire. The assessment covers glazed doorsets and screens within the Ottostumm W40 configuration – integrity only, one side, up to 30 minutes. Architects must confirm that their specific configuration falls within the assessed scope, and Building Control and a fire engineer should review all fire-rated applications before specification is finalised.
How does Fabco support heritage and listed building specifications?
Steel glazing has been used in listed buildings for over a century, and the W20 system’s 10mm sightlines closely replicate original Crittall-era proportions, making it suitable for conservation areas, art deco properties, and period homes. Fabco’s team includes directly employed project engineers who can advise on glazing options – including single glazing for listed applications or slimline 4/10/4 krypton-filled double glazing where thermal improvement is permitted. Guidance on what conservation officers typically require should still come from the architect’s own planning consultant.
Is there a named contact for architects during specification and delivery?
Every Fabco project is assigned a dedicated project engineer who acts as a single point of accountability from initial survey through to installation handover. Surveys are conducted using state-of-the-art 3D laser measurement before production begins. Unlike suppliers who split responsibility across regional installer networks, Fabco employs its surveyors, fitters, and glazing engineers directly, so the architect communicates with one team rather than multiple subcontractors.
What post-installation support is available if issues arise after handover?
Fabco maintains an in-house Customer Service Team and dedicated onsite Customer Service Engineers who handle both warranty and non-warranty issues after project completion. Because installation is carried out by directly employed Fabco engineers rather than third-party contractors, accountability does not fragment at handover. The wet-glazing process uses RAL colour-matched, UV-resistant, colour-fast silicone throughout, reducing the likelihood of cosmetic degradation that can generate post-handover calls on other systems.
Summary
When it comes to premium residential projects, fabricators who employ their own project engineers tend to get the job done right. Fabco’s W20+ system is a good example. It achieves a U-value of 1.3-1.4 W/m²K and carries an A+ rating. Projects using this kind of direct engineering support see fewer mistakes during specification and fewer headaches after handover.
