Secondary Glazing Explained

How it works

Secondary glazing sits 100–200mm inside your existing window, creating a sealed air-gap that dramatically reduces heat loss, noise transmission and draughts. Your original window stays completely untouched — no damage, no altered sight-lines, no planning consent needed.

Why not replacement double glazing?

Replacement is expensive, disruptive, often blocked in conservation areas and rarely acoustically better than a well-specified secondary glazing install. A wider air-gap outperforms a sealed 20mm double-glazed unit for noise every time.

• Wider air-gap = better acoustics
• No planning consent needed
• Fully reversible install
• Fraction of the cost of replacement

What you can expect

Up to 80% noise reduction, up to 65% thermal improvement, elimination of draughts and condensation on the primary window, and installation typically completed in a single day per property.

• Up to 80% noise reduction
• Up to 65% thermal improvement
• U-values from 1.868 W/m²K
• One-day install per property

Where it's used

Victorian and Georgian townhouses, listed properties, converted mills and warehouses, offices near flight paths, hotels on main roads, schools and healthcare buildings across South Yorkshire.