Secondary Glazing

What is Secondary Glazing?

A functional and effective glazing solution

A technique that involves installing supplementary glazing over an existing window, our secondary glazing is supplied in a fantastic range of styles and designs. With a choice between sliding and fixed options, our secondary glazing service improves the functionality of your existing windows.

In this process, a completely separate aluminium frame and glass is installed on the interior portion of the existing frame or window reveal, thereby transforming your single-glaze window into one with a crude form of double-glazing and the associated benefits. The goal of our secondary glazing service is to help you retain the charm and beauty of your original window while improving its practicality.

  • Available in a range of styles and designs
  • Improves the energy efficiency of your home
  • Offers additional security and durability to your existing windows

Fensa Registered Company

FENSA is an acronym for the ‘Fenestration Self-Assessment Scheme’. Set up by the Glass and Glazing Federation, it allows double glazing companies to self-certify compliance with Building Regulations. There are several reasons why you should check for the FENSA logo when looking to have new windows and doors fitted in your home.

QA National Warranties

The insurance intermediary company QANW is responsible for protecting consumers through insurance policies. QANW has been in the business for over 25 years and has formed close associations with various building contractors and trade associations throughout the UK.

City & Guilds - Level 3 Qualified

The educational organisation City & Guilds are known for their vast levels of assessment, offering employees and workforces with the skills they require for many years. This seal of approval provided through their accreditation gives customers the confidence they require. Two of our employees, one in management and the other in our service department are qualified to City & Guilds level 3. This level of accreditation is highly sought after, with City & Guilds working with some of the leading brands of various sectors to offer the highest standard of training. The accreditation offered by City & Guilds is valued significantly, showcasing a business’s expertise, dedication and knowledge. In achieving this level of qualification, customers can feel assured that they are receiving the highest standard of work and customer service. City & Guilds and the City & Guilds logo are trademarks of the City and Guilds of London Institute and used under licence.

Checkatrade - Proud Members

Finding a tradesman is not always an easy task, especially when you’re unsure whether he or she is trustworthy. After all, you’ll be inviting this person into your private home, so you need make sure that they are reliable.

GQA Qualified

GQA Qualifications is an Awarding Organisation for specialist sectors and occupational roles. Qualifications cover the Glass, Construction, Coating and Print industries.

PASMA Tower Trained

Our team are fully trained in the assembling, dismantling, moving and inspecting mobile access towers and working at height.

BFRC Rated

Our products are BFRC rated, an independent verification of the energy efficiency of our windows and doors. BFRC rated energy efficient windows and energy efficient doors carry a ‘rainbow’ label.

  • Security

    Improved security

    Older, traditional window designs rarely provide homes with sufficient security. Secondary Glazing provides a supplementary protective barrier to existing windows; offering additional security and durability. We understand that your home’s security is important, which is why we take great care in installing secondary glazing to ensure your family and home are safe and secure. 

  • energy-efficient


    Secondary Glazing improves the energy efficiency of homes by providing insulation and noise reduction. With almost one-fifth of a home’s heat lost through single-glazed windows, secondary glazing helps reduce the cost of your household bills. If you’re unsure on replacing your existing windows and would prefer to choose secondary glazing, get in touch today to see how we can improve your energy efficiency with secondary glazing. 

  • design window


    Secondary glazing greatly improves the longevity and reliability of your windows by providing a functional barrier from damage and daily wear and tear. As a result, Secondary Glazing is a superb choice for listed and aged buildings. Our team of glass and glazing experts will help you find the best possible glazing solution to fit your needs and budget.

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Benefits of Secondary Glazing

Secondary glazing is famed for its strength, reliability and longevity. Apart from the noise-related advantages, secondary glazing can also be used to make buildings more insulated, improve the quality of air inside your home by reducing the entry of pollutants, dust and (when using specialist glass) UV rays too. Take a look at the benefits below:

  • Fantastic heat insulation properties
  • Effective noise reduction
  • Superb choice for listed and aged buildings
  • Great solution to the inability of installing double-glazed windows and doors
  • Money saved on energy bills.
  • High standard of security

Thermal Advantages of Secondary Glazing

The thermal benefits of secondary glazing are multiple and can dramatically reduce the level of heat that escapes from a property, enabling energy bills to be cut, translating into an excellent investment as a result.

Reduce Your Carbon Footprint with Secondary Glazing

Secondary double glazing is more eco-friendly than replacement double glazing. Due to the fact that you’’ll be placing less reliance on heating appliances if you purchase secondary glazing, you can do your bit for the environment upon signing up for them.

Noise Reduction

Secondary Glazing is noted for reducing noise pollution and removing the irritation that can be faced from traffic or noise from passing crowds. For those looking to keep noise in, such as the owners of pubs and clubs, secondary glazing is the perfect solution.

Draught Reduction

Draughts are another major cause of concern in older properties during the winter months. Strong cold winds seeping in through gaps in windows can easily turn your rooms into a cold chamber no matter how much you spend on heating bills. Secondary glazing acts as an additional barrier between draughty windows and your home.

Reduced Condensation

Build up of condensation on single window panes, due to difference in outside and inside temperature, will make a room damp. This can be accentuated during winter months so you must do all you can to keep your home warm and dry.

Secondary Double Glazing Costs Less Than Replacement Double Glazing

This makes it a perfect choice for those on a budget. Installation costs are generally much lower and the glazing enables you to reinforce your original windows, extending their life and allowing you to get more years of use out of them.

Maintenance of Secondary Glazing is a Breeze

Secondary glazing also requires only a small amount of maintenance, with little else being required other than occasional cleaning to keep them in the right condition. It can even be manufactured with special glass to prevent sunlight from compromising the look of interior items such as photos and furnishings.

Secondary glazing is perfect for those hard to treat areas, allowing easy access for the purpose of cleaning.

Styles and Designs of Secondary Glazing

We have a selection of finishing colours for you to choose from including brilliant white, brown and silver. However, we can also accommodate particular requirements and manufacture secondary glazing in a colour of your choice. As standard procedure, all of our items are glazed with a flexible PVC gasket.

Hinged and Fixed Secondary Glazing

This popular style of secondary glazing is the perfect choice for masking hardwood windows that let in draught air. The heat insulation of your home will be instantly improved and you can immediately start saving money on your energy bills.

Sliding Secondary Glazing

Our sliding secondary glazing choices are of an excellent quality and will add extra comfort and style to any building. At Sheerwater Glass we offer two different styles of sliding glazing – horizontal and vertical – the use of which depends on the size and shape of your window. With fantastic insulation properties these glazing options will save you money on energy bills and match the style of your home perfectly.

Vertical Sliding Secondary Glazing

Many customers opt for vertical sliding secondary glazing for windows that are taller than they are wide. These windows are excellent for eliminating draughts due to the vacuum that is produced between the two units.

Our vertically sliding secondary glazing is designed with Guillotine shoot bolts for minor windows and is Spiral balanced for bigger windows. The use of this secondary glazing is ideal for windows that are taller than what they are wide. A half of the window will slide over the other in a vertical movement. Listed buildings benefit most from this type of unit as they help to eradicate draughts and improve insulation. A vacuum between the two units is created, similar to double-glazing, eliminating draughts and noise pollution. At Sheerwater Glass our sliding windows are also sealed with a twin polypropylene weatherpile for extra insulation and comfort.

Horizontal Sliding Secondary Glazing

Horizontal sliding secondary glazing is the perfect choice for windows that are wider than they are high. These too come with excellent insulation and soundproofing features.

The horizontal sliding action of this option acts similarly to the movement of sliding patio doors. This type of secondary glazing works particularly well with windows that are split vertically into two panes. This allows the bars of our secondary glazing to match the design of your current window. This option is perfect for windows that are wider than what they are high. As with all of our sliding windows, our horizontal range has fantastic insulation and noise reduction qualities.

Finished with a twin polypropylene weatherpile sealant, you can rest assured that your windows not only look amazing, but are extremely secure too.

RAL Colour Chart

Click on the picture below to enlargeSecondary Glazing Colour Chart

No Need to Replace Your Old Windows with Double Glazing – Use Secondary Glazing

Many people residing in older properties have invested in secondary glazing due to the way that it allows them to reinforce their windows whilst retaining their character and charm.

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