Shutter Guides 26.02.18

Do window shutters block out light?

At Diamond Shutters, we consider interior shutters to be one of the best and most versatile window coverings available. They’re modern, attractive and created to fit the needs of customers, no matter the style of their homes. Despite this, one of the questions most frequently asked by prospective buyers is: do window shutters block out light?. It’s understandable as to why people might think that shutters will let light in. There are small gaps between the louvers of shutters that many people assume will allow a lot of light to pass through.

When asked if our window shutters will block out the light, and how much light can be blocked, the answer often varies. However, as a general rule of thumb, shutters will block a substantial amount of outside light from coming into a room.

Will they block out light?

First things first, it’s important to remember that it’s almost impossible to completely block out all light unless your room has no windows or doors. With that said, despite the slight gaps between the louvers of our shutters, they actually provide better blackout capability than the majority of Venetian blinds and lightweight curtains.

When fully closed, window shutters block out a surprisingly large amount of light. This is especially true for shutters with larger louvers. A shutter with larger slats can be used to flood a room with light when opened in the day, while also preventing most light from getting in when closed. As there are fewer slats in a shutter with large louvers, there are fewer gaps through which light can travel. However, if choosing shutters with thinner louvers, there is more space for light to travel in, reducing the blackout capability of the shutters.

Unlike blinds or curtains, shutters are built into a frame that is designed to fit and be sealed into your window frame. As such, there are no edges around the outside of the shutter itself that light could penetrate. With shutters, the only gaps to allow light into the room are those between the individual louvers. Therefore, they are an ideal option for those looking to limit the amount of light able to access a room, without investing in a more unattractive blackout blind.

For total darkness

You may require absolute darkness in a room during the day, but do window shutters block out light enough to meet your requirements? For shift workers and those with babies, interior shutters are still able to fit to your needs. For absolute darkness with shutters, we recommend incorporating a blackout blind into your window set up. Having a blind between the window and your shutters can help to make sure that the room gets as little light as possible. A combination of blinds and shutters will give you about as much blackout as you can get.

If you’re planning on combining a blind with your shutters, consider opting for white shutters. When made for the purpose of blocking out light, darker shutters can cause the room to feel smaller and gloomier than it actually is. This is especially true if you already have darker walls, flooring and furniture present.


Ultimately, despite a fairly common belief to the contrary, interior shutters do have the ability to block out light. When compared with many curtains or Venetian blinds, our shutters are actually the better option for decreasing the amount of light coming into a room. However, for a more substantial blackout effect, you could consider adding a blind or heavy curtain to your window for that excess light prevention.

For more information and guidance regarding interior window shutters, feel free to get in touch with the Diamond Shutters team and we’d be delighted to help!