Sadly, no, not completely. But they can help to reduce it.
First, a little science. Don’t worry, we’ll keep it simple.
Sound is energy produced when things vibrate. It travels outwards from the source until it reaches our ears. Unlike light which travels in short waves, sound travels in long waves which means it can bend round corners, wriggle through the tiniest cracks and openings, and easily make its way through solid materials. Interesting fact, sound travels through solid steel about 15 times faster than air, that’s why enginneers building tunnels will bang on the metal walls to communicate as it’s the most efficient way of transmitting sound.
So now we know that sound cannot be completely obstructed, let’s talk about how we can decrease it.
If you’re building a new house there are lots of modern materials that go into the construction of a house that act to absorb noise, but if you live in an existing home this option is no good.
Before we move on, it pays to know there are a couple of things you can do to help the noise reducing process that aren’t curtain or blind solutions.
Invest in double glazing. We all know the heat retention benefits of such a feature but those double panes of glass also act to keep noise at bay.
And ensure your window caulking is up to scratch. According to the rules of acoustics, a mere 1% gap in the sound barrier transmits 50% of sound, so make sure any gaps are sealed up tight.
As far as curtains and blinds go to make things quieter, if you’re looking to significantly reduce noise you will need to opt for the thickest, heaviest fabric you can, such as velvet or wool. The more layers the better so ensure you get them thermal lined.
For even more noise reduction, consider having a blind AND a curtain over top.
If you only need a little bit of noise reduction and favour a lighter alternative, choose whatever fabric you want but ensure it has the a blackout thermal insulating liner.
The future looks interesting though. A recent breakthrough from EMPA (a materials science and technology lab in Switzerland) is a light, translucent fabric made of modified polyester designed to absorb sound. This will no doubt revolutionise sheer curtains that right now, are purely to filter light.