Fixed & Sliding Secondary Glazing Consumer Guide

4 min read Windows

Secondary glazing systems are available in a wide range of designs and styles, fixed and sliding. Secondary glazing services are available in the form of fixed and sliding options with each style adding its own unique character to your home's overall appearance.

Benefits of Secondary Glazing

  • Great heat insulation properties, leading to a cosier home and savings on energy bills.
  • Effective noise reduction so you're less disturbed by outside noise.
  • Reduces the build-up of condensation on your windows.
  • A superb choice for aged and listed buildings as it usually isn't deemed to affect conservation guidelines.
  • High-security standards.
  • A great alternative for when double glazed windows and doors are not suitable.

There is a wide selection of finishing colours to choose from for your secondary glazing. This includes brilliant white, silver and brown. It is also possible to accommodate specific requirements and manufacture it in a colour of your own choosing.

The standard procedure for many manufacturers would be to have all items glazed with a flexible PVC gasket.

Types of Secondary Glazing

Hinged and Fixed Secondary Glazing

This is a popular style of secondary glazing that is the perfect solution for masking hardwood windows that let in draught air. This immediately improves the heat insulation of your home while saving you money on energy bills.

Sliding Secondary Glazing

Sliding secondary glazing options are designed to introduce additional style and comfort to a building. Generally of excellent quality, two popular styles of sliding secondary glazing are vertical and horizontal, the use of which is dependent on the shape and size of your window. The fantastic insulation properties of these glazing options work to save you money on energy bills, while also perfectly matching the style of your home.

Vertical Sliding Secondary Glazing

Vertically sliding secondary glazing is manufactured with guillotine shoot bolts for minor windows and is typically spirally balanced for larger windows. This type of secondary glazing is ideal for windows that are taller than they are wide. It works by half the window sliding vertically over the other half. This type of unit is most beneficial to listed buildings because they assist in the eradication of draughts while improving insulation. A vacuum between the two units is created, which is similar to double-glazing. This serves to eliminate noise pollution and draughts. Sliding windows may also be sealed with a twin polypropylene weather pile to provide comfort and extra insulation.

Horizontal Sliding Secondary Glazing

Horizontal sliding secondary glazing has a horizontal sliding action, very similar to the movement of sliding patio doors. It works particularly well on windows that are split vertically into 2 panes. In this way, the bars of the secondary glazing are able to match the design of your current window.

This option is ideal for windows that are wider than they are high. Horizontal sliding secondary glazing also provides fantastic insulation and noise reduction qualities. Finished with a twin polypropylene weather pile sealant, you get the peace of mind of knowing that your windows not only look great but are also extremely secure.

Is secondary glazing as good as double glazing?

Ultimately, secondary glazing will be better to suited to some people than double and vice versa. So, we've looked at a range of key considerations to help you decide:

Noise reduction

Secondary glazing is slightly better at reducing the amount of external noise coming into the home than double. This is because the gap between the existing window and the secondary glazing is larger than the two sealed panes of glass you find on double.

Planning permission

If you live in a conservation area or listed building, planning restrictions might prevent you from fitting double glazing. In such cases, secondary is the only option if you want to make your home warmer, quiet and more secure.

Secondary glazing cost

Secondary glazing is more cost-effective to fit. However, double glazing is better at retaining heat in the home. Therefore, it tends to provide better long-term savings on your heating bills.


As secondary glazing requires you to clean 4 panes of glass instead of 2, maintenance times are slightly higher than double.

But no matter whether you prefer secondary or double, we install both here at Sheerwater Glass.

How do you clean secondary glazing?

Cleaning secondary glazed windows is very straightforward; all you need to do is wipe them down using warm, soapy water and a non-abrasive cloth or sponge.

The different types of secondary glazing also have their own features to make cleaning easier; horizontal secondary glazing can be removed from the frame; vertically-sliding versions have a contra-slide feature so you can access both sides of the glass.

Related information:

If you'd like more information on secondary glazing, check out our blog on whether or not DIY secondary glazing really works.

payment payment

Get A Quote

One of our team would be happy to have a chat with you about your requirements, answer any unanswered questions and measure up at a time that suits you to provide you a free, no obligation quote.

Get A Quote
feedback feedback

Our customers say

“Used the Sheerwater team to replace a couple of Velux windows in our converted loft. Really first class experience, great communication throughout, super professional and the installation was the best we've had in terms of fit and finish and (lack of) damage to surrounding areas. Will use again!”Tim Loake
View more reviews on Which?
location location

Areas we cover

Sheerwater Glass provides window installation and repairs throughout Surrey and the surrounding areas of our Woking showroom. If you’re interested in our services, we encourage you to check if we serve customers in your area by simply typing in your postcode.

If you check and find that we don’t serve customers in your area, in some cases, we may be able to help. Please call us to find out more.

Check your postcode