If you're thinking about getting blackout curtains, you might be curious about their ability to keep heat out.

Blackout curtains are a type of window treatment designed to block out all light. They are frequently used in bedrooms to aid in daytime sleep. However, they can also keep heat out of a room. Do dark curtains keep heat out?

Yes! Blackout curtains keep heat out.

Blackout curtains do an excellent job of keeping heat out. They can keep a room up to 10 degrees cooler than it would be without them. That is because they block out the sun's rays, which are responsible for most of the heat in a room.

In this article, we will look at the science behind blackout curtains. Moreover, how they can help you.

Materials Used In Blackout Curtains

Materials Used In Blackout Curtains
Blackout curtains are one continuous layer of blackout fabric and are ideal for rooms that require complete darkness. They are often made from polyester or silk fabric. Blackout drapes are heavier than conventional curtains because the darkest part of the average room is incorporated into the fabric.

Even though curtains are made of slightly heavier fabric, they appear lighter in weight and more like regular curtains than heavy ones. More than one layer of dense fabric with blackout qualities may be in heavier curtains.

Benefits Of Blackout Curtains

Blackout curtains are not only effective at blocking out light, but they can also help to keep heat out. By preventing heat from entering your home through the windows, blackout curtains can help keep your home cooler in the summer.

In addition to keeping your home cooler, blackout curtains can help reduce energy bills by trapping heat inside your home. A few major benefits of blackout curtains are given below:

Save The Room From Draft And Heat

Blackout curtains have a thick liner attached, so they can assist keep your room a little warmer by preventing cold air from seeping through the window (a thermal curtain will be even more successful in this regard).

Additionally, they can help keep the room a little cooler during the warmer months by obstructing direct sunlight.

Manage Energy Cost

Although most people like white curtains, the term "blackout curtains" conjures an image of dark curtains in our imaginations. They possess a thermal benefit and an elegant, sophisticated, and artistic appearance.

This makes them perfect for use as window coverings, as most homes lose an average of 10 to 25 percent of heat energy via their windows.

Installing blackout drapes will result in a 25–30% increase in thermal insulation and energy savings. In the summer, the curtains reflect light and keep heat out of the space, while in the winter, they trap heat and prevent it from escaping.

No External Noise

A blackout curtain can lessen outside noise and prevent light, which is especially useful if you live near a busy street. To appreciate the peace of a quiet room, drawing the curtains helps to create a barrier.

This is useful for professionals who work from home and wish to minimize interruptions. The best part is that those who have trouble falling asleep at night will adore the serene atmosphere the curtains provide, ensuring restful sleep.

Strange noises will not keep you from getting the rest you require for the following day.

Protect The Furniture

Sunlight's ultraviolet radiation can damage or degrade indoor surfaces like carpeting, upholstery, and furniture.

According to interior designer and proprietor Jennifer Hunter Design Jennifer Hunter, blackout curtains effectively create a barrier between the sun and your furnishings by obstructing sunlight.

Optimize Your Blackout Curtains In Winter

Optimize Your Blackout Curtains In Winter

Purchasing premium thermal blackout curtains is a great first move! Try out these suggestions if you want to go beyond in your energy-saving efforts this winter:

  • On bright, sunny days, leave your blackout curtains open to allow the sun's radiant heat to enter your home. Keep the curtains closed at night and on cloudy days.
  • Consider hanging the thickest thermal blackout curtains on windows. Though it may seem contradictory, they do not typically receive direct sunlight. Without sacrificing the warmth provided by the sun during the day, you may stop the unwelcome heat transfer.
  • Choose window-facing curtains with a dark liner to absorb as much heat from the sun as possible. The heat will then leave the area and evaporate. Alternatively, you may suspend a lightweight, dark-colored curtain behind your white thermal or blackout curtains and remove it in the summer.

Is Having Blackout Curtains Preferable?

Blackout curtains will block light better than any other type of curtain, which is its main advantage. Added advantages of blackout curtains include:

Blackout curtains help insulate a room, which increases energy efficiency. Due to their thickness, blackout curtains also assist in reducing outside noise.

You might be facing the issue of high humidity in home, read our blog on how to control high humidity in home.

Things To Consider Before Buying A Blackout Curtain

Numerous aspects must be taken into account while selecting a blackout curtain. Blackout curtains come in various shapes, hues, and materials, and many have sound- and heat-insulating properties. When determining the top curtains, we considered each of these aspects and consumer reviews.

Effective light blocking

A curtain may be marketed as a blackout, but it does not guarantee that it will block 90–100% of the light entering the room. We examined products, reviewed customer evaluations, and looked closely at product review images that demonstrated the proper working of the curtains.

Installation simplicity

The majority of people can install all items with ease. Blackout curtains are available in various textures and materials, from polyester and cotton to velvet and linen. Their team offers a range of solutions to satisfy a buyer's preferences for both form and function.

Customer feedback

Before purchasing any product, check for the customer's review. You should buy if the positive reviews are more than 75%. If there are many negative and abusive comments, just ignore the product.


The majority of blackout curtains cost between $30 and $50. However, the cost of curtains varies based on the brand, quality, and fabric. You should purchase the curtains according to your budget.

Frequently Asked Questions [FAQs]

What kind of curtain blocks heat?

In the short term, thermal curtains can assist prevent cold air from entering via air leaks around your windows throughout the winter.

They aid in stopping chilly air draughts from circulating the space by capturing them behind several layers of fabric.

Can blackout curtains aid in maintaining a cool space?

When placed, blackout curtains and shades can cut the heat that enters a room through windows by up to 24 percent, keeping the space cooler in the summer and warmer in the winter. You will be able to operate your heating and cooling system more effectively and conserve electricity by doing this.

What distinguishes thermal from blackout curtains?

For the most part, blackout curtains are made to block out light from the window to darken a space completely. On the other side, thermal curtains are primarily made to lessen heat loss from a room's windows.


We hope this article has helped answer your question: do blackout curtains keep heat out? While they may not be the most stylish option, blackout curtains are a great way to keep your home cool in the summer.

If you want to save on energy costs, blackout curtains are an affordable and easy solution.

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