Why Does Double Glazing Mist Up on the inside

why does double-glazing mist up on the inside?

Whether at home or in the office, misted double glazing can affect us all. Not only is it unsightly but it can also affect the energy efficiency of your home or business. But why does double glazig mist up on the inside – If you suffer from condensation problems in your double-glazing then read on. We often get asked why does double-glazing mist up on the inside? In this blog we will examine the reasons for the inside mist up, what you can do to prevent it and solutions if you have been unable to reverse the effects.

What Is Double Glazing?

Double glazing is a window that consists of two panes of glass with a thermal spacer bar inside of the glass panes allowing air to circulate. They are all sealed together to create an airtight seal.

The air gap slows down thermal transfer, meaning it helps to retain heat in a room by keeping cold air outside and warm air inside. Ideal for our lovely cold UK winters.

There are different thicknesses of glass you can get in a double glazed unit along with different sized spacer bars depending on your glass specification required. Double glazing can also be filled with argon gas to help improve the energy efficiency in your home.

All new homes have done away with single glazing and since 2002 88% of UK homes now double glazing. New builds are now built with double glazing as standard to comply with building regulations thanks to its many benefits. The main key benefits of double glazing being its thermal properties and noise reduction.

How Is A Double Glazed Unit Made?

Double glazed units consist of two layers of glass separated by a continuous spacer bar which creates a layer of air. This layer of air acts as an insulating barrier.

The spacer bar fitted between the two panes is filled with a desiccant to absorb any residential moisture within the cavity. This prevents condensation from forming between the panes.

The spacer bar is then bonded to the glass and sealed with a primary and secondary sealant making the unit airtight.

What Is Misted Double-Glazing?

When there is condensation appearing in between the two panes of glass of your double-glazed unit, it means water has managed to get in between the glass panes and into the cavity where air circulates.

This leaves a lovely steamy water vapour appearance on the inside of your glass (meaning if you were to touch it, it wouldn’t wipe away).

Not only does it look bad but it also means your window is no longer a sealed unit and will not be functioning as it should. This could result in heat loss and a build up of excess moisture which could lead to mould and mildew which is not good for your health.

Misted double glazed units are not only an eye-sore but are also a tell tale sign that there could be an underlying issue. It could also be a contributing factor to paying out more to heat your home as a result of your units not being properly insulated.

Although it is easy to ignore foggy windows in the summer it’s a good idea to get them replaced before winter when you will be most affected. This may sound expensive but fear not, you are able to just replace the glass itself as opposed to the whole window.

Different Types Of Condensation

Not all condensation appears on the inside of your glass, and not all condensation is an issue. See the 3 main types of condensation on your glass panes below and when it is time to take action.

1. Condensation on the inside of your windows

This occurs when warm air vapour meets a cold surface area, as a result leaving a liquid residue on the window surface. This can be wiped away but if this builds up, over time mould can form. Condensation within your home can be controlled but it is when condensation forms between your double glazing glass that there is a problem.

Contributing factors to condensation inside your home could be to the build up of moisture and humidity. Contributing factors could be drying your clothes inside when it is cold and wet outside, showering with your windows closed, basically poor ventilation where water vapour cannot escape.
Ventilation in your home is very important and will explore this in a moment.

2. Condensation in between your glass

This is a sign your window is blown, misted, foggy, as well as a few other terms used to explain your unit has broken down. Meaning water vapour has made its way in between the panes of glass and into the air cavity.

This is a sign your window is not functioning as it should and needs to be replaced. Fear not the glass unit itself can be replaced as opposed to the whole window.

3. Condensation on the outside of your windows

As the lovely UK mornings get colder, you will notice condensation form on the outside panes of your windows. This is the ideal type of condensation indicating your glass is functioning as it should.

This occurs when warm humid air comes into contact with cold glass. This means your windows are working and keeping warm air in and cool air out to prevent heat loss.

Why Does Condensation Appear?

1. Time

A common and unavoidable reason as to why your double-glazing mists up is time. Over time the desiccant becomes saturated and can not absorb any more water vapour within the two panes.

As a result, this causes a build-up of condensation to appear. Most double-glazing suppliers offer a guarantee against their double-glazing failing, on average anywhere between 5 to 10 years.

2. Poor installation

If your double glazing was fitted recently and has already begun to mist up, the seal could have been broken or compromised in some way.

This could be the result of poor installation. You should contact your supplier who installed the window as this should be under guarantee for a certain period of time. When looking for a double-glazing installer always go with an experienced and reputable company.

3. Chemicals

Over time harsh chemicals can allow water to seep through and break down the window sealant. You should always check the label before using any chemical products on your windows/doors.

The Importance of Ventilation In Your Home Or Business

It is important to make sure you have enough ventilation to help prevent the build-up of excess moisture, which can contribute to condensation in your home or business. Poor ventilation can lead to a range of problems.

Tips for improving ventilation in your home could include:

• Trickle vents in your window frames.
• Gas vents in your glass (these can be fitted into single and double-glazing).
• Opening windows every so often to create air flow.

Is there a quick fix for double-glazing replacement?

There are the odd few glazing companies who offer a quick fix for removing the condensation from the cavity of the unit. This is a temporary measure and only available on a very limited amount of windows. With a broken down double glazed unit usually the only option is to replace it and get a guarantee for the future.

Getting a replacement window

If your double glazing is no longer covered under a warranty, you can contact any glazing company to arrange for a replacement to be made.

• Good news the window frame will not have to be changed and it is just the glass unit itself that can be replaced.
• Price will vary depending on the size of the unit and also the glass specification. There are lots of glass options available today that are more energy efficient so options can be discussed with your glazier to give you maximum results.
• Do your research, find a reputable company that has good, current reviews.
• On average a new double glazed unit can start from £195 + vat* (price is based on size and specification of glass and is subject to view).
• Request a free no obligation quote by clicking here.

Time for a change?

Why does double-glazing mist up on the inside? Now we have answered this question in this blog, the important takeaway is that your double-glazing does not just have to be misted up for you to replace it.

Double glazing can be replaced if it is damaged on one side or both, or if you just simply want to upgrade it with something new and more energy efficient.

Aaran Glass have a team of reliable and experienced glaziers throughout London and Surrounding areas to help upgrade your existing double glazing to suit all of your needs for your business or home.

Glass specifications include:

• Clear glass
• Obscured glass
• Toughened glass
• Laminated glass
• Softcoat glass
• Tinted glass
• Acoustic glass
• Glass with window film
• Fire rated glass
• Solar control glass
• Self clean glass
• And much more

Double glazing for your home and business, Aaran Glass specialise in double glazing in:

• Windows
• Doors
• Roof glass
• High-level glazing
• And more

Click here to get in touch to find out how we can help.