How to Check Efficiency of Double Glazing

How to Check Efficiency of Double Glazing

Double glazing is far better than single glazing for insulating your home. It also offers better protection from sound pollution. But how do you know if your double glazing is still working effectively?

Double glazing has a flexible lifespan, with some windows lasting for just 10 years before they need to be replaced and some lasting for 50 years before they start to fail. If you are energy conscious and want to ensure that your home is as efficient as possible, you may want to know how you can be sure your windows are still working as they should.

How efficient is double glazing?

Double glazing is more efficient than single glazing at retaining heat, but not as efficient as triple glazing. Most modern double glazing windows have an energy efficiency rating of A+ and this is on a scale of A to G. When choosing your double glazing, you need to think not only about the costs of installation, but the potential higher costs of heating your home if you choose a cheaper, lower grade window.

How do I know if my windows are energy efficient?

How do I know if my windows are energy efficient?

The first thing to do to find out how efficient your windows are is to check with the manufacturer. If they are fairly new, they may still be under some kind of guarantee. This should tell you the minimum level of energy efficiency you can expect, but this doesn’t rule out the possibility of poor installation or faults in your windows making them less efficient.

How do I know if my double glazing is failing?

If you think your home is less cosy than it usually is, and you haven’t made any other major changes to the insulation or window coverings, then your double glazing might be to blame. Windows can drop in the frames, leading to less efficient seals which can make your home feel less warm and comfortable.

There are a few different things you can try to check if your double glazing is still working as it should. Try these methods to test the efficiency of your windows.

Light a match

Light a match

The first thing you can try is to look for draughts around your windows. A simple way to do this is to close your windows and isolate a single room so you don’t have any through draughts. Next, light a match or incense and hold this close to the window. If you notice the match is flickering or the smoke from the incense is billowing, this could be a sign that there are faults in the seals around your window panes or around the frame. Move the match or incense around to help identify the spot.

Monitor your energy bills

Keep a close eye on your energy bills to spot if you are using more energy without changing your usage. If this is happening, it could be a sign that your central heating has to work harder to achieve the same results. If your heating is set to a timer, and you haven’t increased the temperature on the thermostat, but your bills are rising, this could be a sign that your double glazing isn’t working as efficiently as it could be.

Use a thermometer

Use a thermometer

You can see how long a room stays warm – and therefore see how efficient your heating and other insulation measures are – by using a thermometer. Place this in the same spot in your home and then switch on your central heating. Once you switch off your heating, watch the thermometer to see how quickly the temperature falls. 

If it drops quickly, you might have a broken seal around your windows that is letting cold air into your home and allowing warmth to escape. Remember there could be other factors impacting the energy efficiency of your home, including insulation and draught proofing measures.

What can you do to make your windows more efficient?

What can you do to make your windows more efficient?

If you suspect your windows aren’t working as they should, the first thing to do is to check if they are still under warranty. You might be covered for manufacturing faults that occur within the warranty period.

Next, you should check that the windows are positioned correctly in the frame. If you struggle to open or close your windows, or if you notice cold air around your window, this could be a sign that your windows are not forming a perfect seal. You can move the windows in the frame to get a better fit.

And finally, you can also replace the seals around your windows, especially if you notice draughts. Broken seals can lead to condensation buildup between the panes so this should be addressed as a matter of urgency. If you notice condensation, you will need to repair or replace the impacted panes before you address the seals.

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