We are leading suppliers of high-quality secondary glazing across the UK. With over 20 years of experience and an average rating of 4.9/5, our expertise shines throughout our product range.
10-Year Guarantee • Manufactured in the UK • 200+ RAL Colours • 4.9 Reviews
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:
The Measuring Process is easier than you may think, whilst very important it does not require pinpoint accuracy as not all windows fit standard shapes.
The idea is to ensure when fitting into a reveal or within a frame boarder, the unit is slightly smaller than the tightest narrowest points. this ensures the unit will fit and gives some room for adjustment, we recommend a 10 mm tolerance deduction to the total measured width and height, this is the build size of the frame and the sizes used to get a quote. Gaps and distortions around the frame are all hidden and sealed by the Edging Trim.
See The Measuring Guidance for more information and additional links below:
If you are surface mounting around a window reveal to the internal wall sash windows l or around a glass panel (face fixing) – you will need to ensure the frame is wider than the recess to get a fixing into the frame/face of the area being treated, this would be adding the width of the frame on each of the four sides of the window – unit frame size details can be accessed in the Product Brochures.
Most of our business is to the DIY market, Units are supplied fully assembled, predrilled and glazed, easy installation ready.
If you follow the simple step by step Measuring Guide, the units will easily lift into position, with a few adjustments to get level, all of which is fully explained in the Installation Guide, the units can be fixed in place and the supplied finishing trim applied to cover, seal and hide any gaps and inaccuracies between the wall and frame.
If you haven’t got a contact you can rely on we can suggest using the Which Trusted Trader search service, just enter your postcode and search for Carpenter /Joiners, you should get a list of qualified and verified tradesmen in your area and whilst we can’t offer Personal recommendations, they will be more than capable of carrying out the work.
Yes, we can provide most glass types, based on the specific needs of your project. The thickness of standard glass is 4 mm toughened, This safety glass is a minimum requirement where building regulations demand health and safety considerations, including the distance from floor and doors. All our glass options conform to BS6206: 1981 / BS EN 12600 for impact resistance. We do not offer float (non-safety glass). Subject to panel size this may default to a thickness of 6 mm toughened. Laminated, Acoustic, Thermal Low-E, and Obscure glass options can be accommodated. The standard for Sliding, Lift-Out, Hinged & Insert panels are single glazed.
This ensures the frame profiles are manageable size to operate as an unobtrusive secondary window, creating a double-glazed arrangement with the primary window. This offers significantly higher soundproofing performance than double glazing (which is a poor acoustic barrier) thermally it will offer equivalent thermal performance to many double-glazed products – see the performance data in the Help Centre
See our Full Glass Ranges options
What is Low-E Glass?
Low-emissivity glass (or low-e glass as it is commonly referred to) is a type of energy-efficient glass designed to prevent heat escaping through your windows to the cold outdoors. Low-e glass such as Pilkington K Glass™ Range has an invisible coating which reduces heat transfer and reflects interior heat back into your room. This can offer a 5-10% increase to the thermal insulation performance of a non-coated glass.
With secondary glazing it is a hard coat application, it has a robust quality, but can be scratched if abrasive materials are used to clean the glass, see maintenance.
What is Laminated Glass & Acoustic Laminate Glass.
Both are basically the same structure, with 2-layers of glass sandwiching a polymer sheet, the plastic film is usually 0.4 mm or 0.8 mm thick, so a 6.4 mm laminate is 2 layers of 3 mm glass either side of a 0.4 mm film, an 8.8 mm laminate is 2-layers of 4 mm glass either side of an 0.8 mm film.
With a standard laminate, the plastic layer will increase impact resistance and a high performing safety / security option. With the Acoustic Options, it is exactly the same make-up, but the polymer liner is a material called Polyvinyl butyral (PVB) which enhances the ability to absorb and dissipate the sound energy within the glass structure more effectively. Obscure glass options are available but priced on application.
Obscure glass options are available but priced on application.
It is difficult to give exact details, as every property and everybody can be affected differently by noise pollution, however the science confirms, Clearview Secondary Glazing can reduce noise by as much as 80% or by over 50 decibels, (a reduction of 3dB is equivalent to halving the noise energy) this is 5 times greater than either double or triple glazing. This is subject to final specification and installation limitations, these details can be clarified during a consultation with one of our advisors. But the number one target is to try and put as much space between the existing glass and new secondary glazing kit, The bigger the air-gap, the better the performance. If the space allows, try and get 100 mm + to an optimum 150 mm to 200 mm. where space is limited a thicker glass will help. We always recommend starting with a 6 mm glass for soundproofing.
Soundproofing for comprehensive information
We have test certification which confirms that Clearview Secondary Glazing can enhance the thermal insulation of a single glazed window by as much as 65% or a U-Value of 1.868 W/m2K (a U-Value is the formula for measuring heat loss the bigger the number the more inefficient the window is, a standard single glazed window has a recognised U-Value of approx. 5.8 W/m2K). This performance is better than a Class C, with some products this performance can be as much as A+. English Heritage and Historic Scotland carried out research through Glasgow University which showed secondary glazing out performed double-glazed replacement windows. This is subject to final specification and installation limitations these, details can be clarified during a consultation with one of our advisers. See our Thermal Insulation pages.
The cost of secondary glazing varies depending on factors such as the size of your windows, the type of glazing chosen, and the complexity of the installation. Typically, prices start from £163.66 per window, making it a more affordable alternative to double glazing. Investing in secondary glazing not only reduces energy bills but also enhances comfort and property value. Secondary glazing is a cost-effective solution for improving energy efficiency, sound insulation, and security in your home, get a quick and easy quote to find out what it will cost you.
Yes, for many homes it is a great upgrade that provides a wide range of benefits from cost-saving to value added. This means your return on investment is almost guaranteed, and you won't regret getting it installed. Especially if your home suffers from condensation, draughts or noise pollution.
Yes, whether you're an avid DIYer or a beginner, any secondary glazing kit in our product range can all be fit by you if you have a few tools and some spare time.
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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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