Why Do Windows Make Cracking Sounds at Night? (Five Reasons)

Most sounds are suspect if they are heard at night.

A cracking window at night can mean a burglar is out and about or a window is sizing down to its right size after the day’s sun. The cause doesn’t matter much until you establish it.

But, Why Do Windows Make Cracking Sounds at Night?

There are several explanations for that. Foremost, it’s likely that your windows are contracting as a result of the dropping temperature. During a hot day, parts of your windows may expand slightly. When sunset occurs at the end of the day, the temperature drops. This could be the cause.

Five Reasons Why Your Windows Are Noisy

1. Your New Windows Are Settling

Are they new windows? If so, they are likely taking their real shape and will quieten soon.

Chances are you used wet or ‘green’ wood that ended up shrinking.

How Can You Tell?

Inspect the weather-stripping or gap between the sash and jamb.

If it’s not consistent throughout the window, there’s a strong likelihood your windows are settling, hence the noise.

The faster the settling the louder the noise. This means you wouldn’t hear anything if the windows took their time to settle.

However, while settling is normal, it can progress into a major problem that may need urgent correction before it’s too late.

2. Aluminum Windows Or Cladding On Windows

If your windows are made from aluminum or have aluminum cladding on them, it’s likely the aluminum itself is to blame.

Aluminum is a unique construction metal when it comes to thermal expansion.

High Thermal Expansion Coefficient Than Most

Let’s compare aluminum to steel, for example – the thermal expansion coefficient for aluminum is 23 whereas that of steel falls anywhere between 11 – 14.

This means that, if the two were to be exposed to a given temperature, aluminum will expand twice than steel.

Thermal expansion for aluminum is 35% more than what you find in copper.

But how?

Because of its high thermal expansion coefficient, aluminum expands and contracts easily.

Often, temperatures drop by a wide margin as the hot daytime transitions into a cold night, causing your aluminum windows to produce a cracking sound.

3. Could It Be Your Low Emissivity Glass Windows?

When did the problem start?

If it only became apparent after you had replaced your regular single-pane windows with low-emissivity (often “Low-e”) windows, then the replacement is a probable culprit.

What’s “Low-e” Glass?

UV light is bad for your skin and can tarnish some fabrics as well.

As such, sunscreen is to your skin what Low-e glass is to your windows – they keep UV light at bay (although Low-e glass eliminates infrared as well).

The Low-E glass comes with a super-thin coating on them to reflect heat and UV light in the atmosphere.

How Do They Even Produce The Crack?

First off, be certain not to mistake double-glazed windows with Low-E windows – the former reduces outside noise whereas the latter doesn’t. The latter may end up producing noise.

The cracking sound is often instigated by the extra thin, heat-reflecting, coat.

The reflected UV light and heat can make the surroundings hot enough to affect nearby metals.

If the nearby metallic parts are unfortunate to have a high thermal expansion, they will absorb enough heat to expand and contract when the temperature drops. This may produce a cracking sound.

What’s The Solution?

There’s no solution to noisy Low-e glass windows, unfortunately.

If you are committed to preventing UV light and heat, you have no choice but to put up with the bad side of the glass.

4. Vinyl Siding Installed Incorrectly

Vinyl sidings are pieces of plastic installed for either weatherproofing or decoration or both. They can mimic anything from wood to bricks.

The issue here is that you might be tempted to go the DIY route and save some money.

I wouldn’t advise anyone to install their own vinyl siding unless you are sufficiently experienced.

One of the errors commonly made during installation is nailing them too tightly into the wall.

Give Your Siding Enough Space To Expand And Contract

Tight vinyl sidings could be the reason behind those scary night-time cracking sounds on your window area.

Very much like any other material with a high thermal expansion coefficient, the vinyl used to make your sidings may expand and contract erratically depending on the rate of decline from daytime temperatures to nighttime temperatures.

What’s The Solution?

Uninstall your vinyl siding and reinstall them afresh, leaving expansion slots this time.

Every manufacturer worth their salt will provide instructions complete with the size of space allowed between two sidings.

5. Your Windows Are Old

Listen again! If it starts with a cracking noise before progressing into a whistle, then we can be almost certain we’re dealing with something bigger than an easily solvable flaw.

A whistling window can mean one or several of three things:

  • That your window’s weather-stripping is wearing out
  • That you didn’t install your windows the right way
  • That your windows have seen better days and this is the best time to replace them.


To summarize everything, if your windows produce cracking sounds at night, don’t fret.

It’s most likely to be a result of the normal expansions and contraction of the metallic parts.