SECONDARY GLAZING · DIY OR PROFESSIONALLY INSTALLED
Create warmer, quieter rooms without replacing the windows you love. Order online for DIY installation or choose our professional survey and fitting service.
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Secondary glazing is a second custom-made window, attached to the inside of your existing window, creating a double-glazed effect, without damaging or changing your original windows. Clearview secondary glazing is designed to be discreet and compliment the appearance, décor style and property type. See our product range for more information.
Aluminium secondary glazing provides a number of benefits over standard options.
Whether it’s the long term value and durability that comes with aluminium or the discreet and customisability that comes with it. On top of that, you get:
Beautiful & discreet frames – slim aluminium sight lines, colour-matched frames, professional trims.
Quiet & comfortable living – when specified with acoustic laminate and a generous air gap, it is widely recognised as highly effective for noise and warmth in historic and modern homes.
Resistant materials – with glass and frames built to withstand the day-to-day wear and tear that a busy family life brings to any home.
Horizontal sliders are suitable for various structures, including business, residential, heritage, and listed buildings. Clearview’s horizontal slider systems reduce noise pollution, provide better sound insulation, and come with a 10-year warranty.
Vertical sliders are easy to manipulate and durable, with all the same benefits, such as thermal insulation. Tilt-in models can move back and forth around 35 degrees, which is beneficial for cleaning and crucial for fire safety. All Clearview’s product styles work with the vertical slider.
The hinge casement units from Clearview are an excellent option for many homes. They are suitable for commercial, residential, heritage, and listed properties, and do not obstruct the view or alter the character of the existing primary window. They are custom-made and can open from the side or bottom.
Follow our proven 3-step process to transform your property with professional secondary glazing installation. From initial measurement to final installation, we guide you through every stage of your secondary glazing journey.
Get accurate measurements for your personalised quote. Our detailed measurement guide ensures precise sizing for optimal secondary glazing performance and energy efficiency.
Receive an accurate, no-obligation quote for your project. Our transparent pricing ensures you know exactly what your investment will cost.
Select between DIY installation or professional installation service. Our secondary glazing units are designed for easy installation, while our professional team ensures perfect results.
Clearview offers both options and there is no wrong answer. Whether you prefer to fit your own or have our team handle everything, you get the same high-quality, made-to-measure product backed by a 10-year guarantee. The decision usually comes down to budget, confidence, and the complexity of your windows.
| Factor | DIY Secondary Glazing | Professional Installation |
|---|---|---|
| Cost | + Lower overall cost. You pay for the product only, with no labour charge added on top. | - Higher upfront investment. Labour and fitting costs are in addition to the product price. |
| Time required from you | - A few hours per window. Most units fit in under two hours once measurements are done accurately. | + Minimal. Our team handles everything from arrival through to clean-up. |
| Skill level needed | Basic DIY confidence. If you can use a drill and a tape measure, you can fit Clearview secondary glazing. | + None required. Our certified fitters take care of the full job. |
| Finish quality | + Excellent, provided measurements are accurate. Kits arrive pre-assembled, pre-drilled, and include all finishing trims. | + Consistently high. Our fitters have installed hundreds of units across all property types. |
| Product guarantee | + 10-year product guarantee on all Clearview units. | + 10-year product guarantee plus a separate installation warranty. |
| Support available | + Specialist support team, detailed measuring guides, step-by-step installation videos, and a Help Centre available throughout. | + A dedicated point of contact from quote through to completion. |
| Lead time | Typically 2 weeks from order to delivery. You install at a time that suits you. | Subject to fitter availability in your area. We work around your schedule where possible. |
| Complex or non-standard windows | Standard windows are well within reach. For arches, bays, or unusual shapes, our team can advise on approach before you order. | + Our fitters have experience with all window types including arches, angled bays, and heritage frames. |
| Best suited to | Homeowners comfortable with basic DIY who want the best value from their secondary glazing. | Those who want a hands-off service, have complex windows, or prefer a fully managed installation. |
Secondary glazing is not a one-size-fits-all product. The right choice depends on your window type, what you want to achieve, and the performance level you need. These are the key factors that make the biggest difference to your results.
The single biggest factor in soundproofing performance is the gap between your existing window and the secondary glazing unit. Double glazing has a typical gap of 12mm to 20mm. Our systems can achieve 100mm to 200mm or more. For noise reduction, aim for at least 100mm. Where space allows, 150mm to 200mm delivers the best results. A thicker glass helps further where space is tight.
All Clearview systems are approved for use in Grade I and Grade II listed buildings and conservation areas. When planning permission rules out double glazing entirely, secondary glazing is often the only effective glazing upgrade available. It preserves the exterior appearance of the building while delivering all the thermal and acoustic benefits from the inside.
Standard 4mm toughened safety glass is included as default and meets all building regulations for impact resistance. For noise, we recommend upgrading to 6.4mm or 6.8mm acoustic laminate glass, which uses a PVB polymer interlayer to absorb and dissipate sound energy. For heat loss, Low-E glass applies an invisible coating that reflects interior heat back into the room. These can also be combined. We will advise on the right specification for your situation.
People often ask how it measures up against double glazing. For soundproofing, our systems are significantly more effective. This comes down to the air gap. Double glazing has a typical gap of 12mm to 20mm, whereas this option commonly achieves 100mm or more, creating a far more effective acoustic barrier.
Research carried out through Glasgow University for English Heritage and Historic Scotland confirmed that secondary glazing outperforms replacement double-glazed windows for thermal efficiency in traditional buildings. Clearview test certification shows it can improve the thermal insulation of a single glazed window by up to 65%, achieving a U-value of 1.868 W/m2K from a typical starting point of 5.8 W/m2K for single glazing.
For noise specifically, our range can reduce outside sound by up to 80%, or over 50 decibels. That is five times greater than either double or triple glazing.
Clearview manufactures six core types of secondary glazing, all made to measure for your exact window dimensions:
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"We have a large stain glass window at the front of our house and needed a solution to retain heat and keep out noise. Clearview's Secondary Glazing has made a massive improvement. We are really impressed it even seems to have eliminated our condensation."
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