4-20-4 Double Glazed Unit (Low-Iron / Low-E)

Description

This premium double-glazed unit is engineered for superior clarity, durability, and thermal performance.
Combining 4mm low-iron outer glass, a 20mm argon gas-filled cavity, and 4mm Low-E inner glass, it offers exceptional energy efficiency while maximising natural light transmission.

This unit is suitable for homeowners, builders, and installers looking for a modern, high-performance glazing solution that delivers clarity, strength, and long-lasting performance.

Key Features

4mm Clear Low-Iron Glass (Outer Pane)

• Reduced iron content for superior clarity
• Brighter, more neutral colour compared to standard float glass
• Ideal for installations where natural light and visibility matter

20mm Argon Gas-Filled Cavity

• Argon significantly reduces heat transfer
• Helps achieve improved U-values and energy savings
• Supports a comfortable indoor temperature year-round

4mm Low-E (Low Emissivity) Glass (Inner Pane)

• Reflects heat back into the room
• Helps reduce winter heat loss
• Improves overall thermal insulation without reducing clarity

Warmedge Black ThermaBar Spacer

• Warm-edge spacer minimises thermal bridging
• Helps reduce condensation around the edges
• Modern black finish for a clean, sleek look
• Increases overall unit durability and lifespan

Glass Type Options

Toughened (Default Selection)

• Stronger and more durable than standard annealed glass
• Breaks into small, safer granules instead of shards
• Recommended and often required for doors, low-level glazing, patio units and high-traffic areas
• Default selection in the product glass-type attribute

Annealed (Optional Alternative)

• Traditional non-toughened glass
• Suitable for non-critical areas and installations not requiring safety glazing
• Can be selected manually via the attribute dropdown

Benefits

• Excellent thermal performance with Low-E inner coating
• High clarity thanks to low-iron outer pane
• Reduced condensation due to warm-edge spacer technology
• Helps maintain indoor comfort and reduce energy bills
• Manufactured to industry standards for durability and safety

Typical Applications

• Replacement window units
• Bi-fold and sliding doors
• Conservatories & garden rooms
• Residential and commercial windows
• Modern architectural glazing
• Anywhere requiring thermally efficient sealed units

Estimated Delivery

Estimated delivery: 2–3 weeks.
We will email you the after you place your order.