As architects and homeowners push for ever greater transparency and larger openings, the sliding door has become the defining threshold of contemporary residential design. The Fluid X Sliding Door — the flagship minimal sliding door from UK glazing specialist Fluid Glass — answers that brief with a 21mm central sightline, glass panels up to six metres high, and evidenced thermal performance, all designed, engineered, fabricated and installed in-house.
Glass, not frame
The Fluid X sliding door holds a 21mm central sightline – reducing to just 6mm on its I-View interlock – with concealed frames and a flush, hidden threshold, so the glass reads as an unbroken plane from floor to head. Two glazing options suit any brief: the double-glazed system carries panels up to 5m high, 12m² and 600kg per leaf, while the triple-glazed system reaches 6m, 18m² and 1,000kg. Configurations include open corners with no post between the panels, pocket doors that slide into the wall, curved and sloped runs, and manual or motorised operation – so the same detail can scale from a modest opening to a full glazed elevation.
Evidenced performance for the Future Homes Standard
Behind the minimal aesthetic sits measured performance. The Fluid X achieves whole-door U-values from 1.1 W/m²K double-glazed and 0.8 W/m²K triple-glazed, with acoustic insulation up to 41dB and class-leading weather ratings — air permeability Class 4, wind resistance Class C5 and water tightness up to Class 9A. Discreet multi-point locking can be specified to PAS 24, and low-level glazing meets Approved Documents K and L. Rather than estimate, Fluid Glass provides the evidenced U-value for each configuration, so specifiers can document compliance with confidence as the Future Homes Standard approaches.
About Fluid Glass
Fluid Glass is a British specialist in architectural and structural glazing, based in Watford and working across London and the UK. Founded in 2022, the company designs, engineers, fabricates and installs everything in-house — from minimal sliding doors to frameless structural glass walls, glass box extensions, rooflights and steel-look windows and doors. A member of the Glass and Glazing Federation, its work has featured in Dezeen, Wallpaper*, ArchDaily and the RIBA Journal, and its coastal new-build Orchard House was Highly Commended at the Sussex Heritage Trust Awards 2026.
To discuss a project, request technical drawings or performance data, contact Fluid Glass at sales@fluid.glass or 020 8156 7290, explore the full collection, or book a visit to the Watford showroom.
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Structural
