About Clear Sealed Units Ltd
Trade-only IGU manufacturer — High Wycombe, Buckinghamshire
Who We Are
Clear Sealed Units Ltd (CSU) is a trade-only manufacturer of sealed glass units based in High Wycombe, Buckinghamshire. We have decades of experience supplying glazed units to glazing contractors, window fabricators, construction companies, and architects across the UK.
Our production facility runs five days a week. Glass arrives as raw jumbo sheets from Pilkington, Saint-Gobain, Guardian Glass, and AGC; each unit leaves as a finished, gas-filled, dual-sealed product — typically within 3–5 working days.
As a trade-only supplier, we work exclusively with businesses: glaziers, window companies, builders, housebuilders, and commercial contractors. We do not sell direct to the public.
Our production range covers more than 20 unit types — from standard 4/20/4 DGUs (optional argon fill) and triple-glazed Passivhaus units to acoustic, fire-rated, shaped, and smart-glass configurations. Minimum pane area 0.10 m²; maximum 6,000 mm × 3,210 mm jumbo.
Every unit ships on our own A-frame delivery vehicles or specialist pallet couriers, with real-time tracking and direct-to-site delivery available.
THE PRODUCTION LINE
Made in High Wycombe, Buckinghamshire
Every unit is manufactured to your exact specification in our High Wycombe facility. Glass arrives as jumbo sheets from Pilkington and Saint-Gobain; it leaves as a finished, gas-filled, dual-sealed unit — typically within 3–5 working days.
THE PROCESS
From Raw Glass to Finished Unit
Spec’d to Order
Every unit is manufactured to your exact dimensions, glass specification, spacer width, and gas fill. No stock units — everything is produced fresh to order from verified-specification glass.
Made in High Wycombe
Cut, washed, spacer-applied, pressed, argon-filled, and dual-sealed in our Buckinghamshire facility. Full QC inspection before dispatch. Precision gas fill and sealing systems.
Delivered on Our Racks
Sealed units travel on our own A-frame delivery vehicles — no third-party pallets that risk breakage. We deliver to site, kerb, or store, with typical lead times of 3–5 working days.
What We Manufacture
Standard DGUs
4/20/4 and 4/16/4 double-glazed units with warm-edge spacer and optional argon fill. Centre-pane U-values from 1.1 W/m²K.
Triple Glazed
4/16/4/16/4 TGUs for Passivhaus and high-performance projects. Centre-pane U-values from 0.5 W/m²K with two argon cavities.
Shaped Units
Arched, circular, triangular, and bespoke shaped sealed units cut precisely to your template or CAD drawing.
Acoustic Glass
Laminated acoustic units reducing noise by up to 45 dB Rw. Suitable for road-facing, railway, and urban locations.
Fire Rated
EW30, EI30 and EI60 fire-rated units. Suitable for compartment walls, screens, and doors.
Jumbo Units
Up to 6,000 mm wide — curtain wall, structural glazing, roof lanterns, and other large-format commercial applications.
GLASS SUPPLIED BY
COMPONENTS SUPPLIED BY
Our Trade Customers
Glazing Contractors
Our core customer base. Fast 3–5 day turnaround, trade pricing, and accurate units every time. Open accounts available.
Window Fabricators
Supply sealed units to complement your profile fabrication. Consistent quality and reliable delivery, week in, week out.
Builders and Developers
New-build and refurbishment projects. Volume pricing available for larger programmes; project scheduling on request.
Architects and Specifiers
Technical support, U-value calculations, and sample units to assist project specification. NBS clause on request.
Ready to Work With Us?
Trade accounts welcome. Get an instant online price or speak to our team about your project.