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Glass & Glazing

Specialist glass and glazing systems engineered for performance — warmer rooms, quieter homes, safer openings and lower bills, year after year.

The Glass

Secondary Glazing

Secondary glazing is an internal pane fitted inside an existing window — preserving the original frame and glazing while dramatically improving thermal and acoustic performance. It's the go-to solution for listed buildings, conservation areas and period properties where replacing the original windows isn't possible (or desirable).

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Secondary Glazing
Heritage Windows, Modern Comfort
Why It Matters

Heritage Windows, Modern Comfort

Our secondary glazing systems are designed to be as discreet as possible — slim aluminium frames in a matching colour, with sliding, hinged or fixed configurations to suit the original window. Once installed, they're virtually invisible from outside while cutting heat loss in half and reducing external noise by up to 80%.

  • Preserves original windows & frames
  • Approved for listed buildings & conservation areas
  • Up to 80% reduction in external noise
  • Slim aluminium frames, virtually invisible
  • Sliding, hinged or fixed configurations
  • Easy to remove for window maintenance
Energy efficiency rating
Energy Rating

Improved Thermal Performance

Secondary glazing typically achieves combined U-values of 1.5–2.5 W/m²K when fitted in front of single-glazed windows — comparable to mid-spec double glazing. Combined with existing double glazing, it further reduces drafts and heat loss.

How To Verify

Secondary glazing isn't typically BFRC-rated as a standalone product. Ask your installer for the combined U-value with your existing windows, and the expected dB noise reduction.

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  • FENSA-registered installers
  • 10-year insurance-backed guarantee
  • Over 30 years of expertise
  • Free, no-obligation site survey
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Secondary Glazing — common questions

Yes — secondary glazing is one of the most common upgrades approved for listed and conservation-area properties, because it doesn't alter the original window. We'll handle the listed building consent application on your behalf if required.
Significantly — typically a 50-80% reduction in perceived noise, depending on the gap between the original window and the secondary pane (wider gaps perform better). For homes near busy roads, railways or flight paths, it's often more effective than triple glazing.
No — the secondary pane is mounted on its own frame fixed to the internal reveal, so it doesn't touch or modify the original window. It can also be easily removed for window maintenance, cleaning or restoration.
Secondary glazing combined with original single-glazed windows typically achieves a U-value of 1.5–2.5 W/m²K (vs 4.8 for single glazing alone). That's similar to mid-spec double glazing — a massive improvement on the original window.
Not particularly — modern systems use slim aluminium frames in colours matched to the original window. From outside, the secondary pane is virtually invisible. From inside, it's a discreet second layer that most visitors don't even notice.
Yes — sliding, hinged or lift-out configurations are all available. Most customers choose hinged or sliding for ventilation, with lift-out systems used where the original window is only occasionally opened.

More in Glass & glazing

Double Glazing

Double Glazing

A-rated double glazing fitted in uPVC, aluminium and timber frames — the modern UK standard for warmer rooms and lower bills.

Laminated Glass

Laminated Glass

Laminated safety glass — bonded with a tough interlayer that holds the pane together when broken, for security, safety and sound control.

Low-E Glass

Low-E Glass

Low-emissivity glass with a microscopic metal coating that reflects heat back into the room while letting daylight pass through.

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From residential homes to commercial buildings, we deliver high-quality glazing solutions with expert craftsmanship. Every project is carried out with precision, durability, and meticulous attention to detail.

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