Blackout Curtains Vs. Thermal Curtains: What’s The Difference?

Wednesday, 24 September 2025

Functional curtains are a hugely important part of any interior design project. Whether it’s a home, hotel or anything in between, curtains have practical purposes as well as aesthetic ones. Among the options available are thermal and blackout curtains. While these often have similarities in appearance and weight, there are crucial differences that need to be considered when making a purchasing decision. Let’s explore the difference between blackout curtains and thermal curtains.


What are blackout curtains?

As their name suggests, blackout curtains are specially designed to block out light. The dark and private environment they create makes them ideal for bedrooms, home cinemas or any space where light control is needed. They’re usually made from dense and tightly woven fabrics, think polyester or microfibre.

Blackout curtains typically have multiple layers to effectively block light penetration. Having a dense composition also makes them good insulation against noise and temperature fluctuations. The indoor environment is therefore, quieter and more comfortable.

Beyond these functions, blackout curtains are energy efficient. Their composition and structure mean that they reduce heat loss during the colder months and minimise heat gain when it’s warmer. This makes them well-suited to rooms that benefit from a consistent temperature. Children’s bedrooms and hotel rooms, for instance benefit greatly from blackout curtains.

Our Unity fabric is a superb double-sided blackout with colour on both front and back so both inside and outside have a strong focus. This fabric allows for 100% blackout.


What are thermal curtains?

Thermal curtains are insulated curtains. They provide a barrier against heat transfer and regulate room temperature. Thermal curtains are usually crafted from heavyweight fabrics like velvet, cotton or thermal lining materials like acrylic foam, polyester or fabric blends.

The composition of thermal curtains means they possess insulating properties that help trap heat inside during the cooler months of the year. These properties also mean that they block out heat from the sun when drawn during the warmer seasons. Thermal curtains often have multiple layers of different materials or a special thermal lining, which reduces thermal conductivity. This makes them energy efficient as they help reduce heating and cooling costs.

Aside from temperature regulation, thermal curtains are also good for sound insulation and they help create a quieter indoor environment. This means they’re great for spaces like bedrooms, living rooms and home offices where you want to minimise external noise too.


Key differences between blackout and thermal curtains

The difference between blackout curtains and thermal curtains include their functionality, fabric composition, construction and suitability for different spaces. The light control of blackout curtains makes them effective at blocking out external light to create a dark and private environment. Blackout curtains are constructed in layers using tightly woven fabric and often an additional blackout lining.

Thermal curtains, on the other hand, are designed to regulate temperature by providing insulation against heat transfer. They are made with heavier fabrics and have a thermal lining inside.

While blackout curtains are commonly found in bedrooms due to light control, thermal curtains are suitable for any room where you’d like to maintain a comfortable temperature.


Which curtains are right for your needs?

When choosing curtains, you’ll need to consider several factors. Firstly, consider the main function of the curtains in the room. Are you looking to prioritise light control, temperature regulation, or both? When you understand the space requirements and priorities for your curtains, it can help you decide which ones are best suited.

You’ll also need to consider your budget too. Although blackout curtains offer superior light-blocking capabilities compared to thermal curtains, they often come at a higher cost. Balancing your needs with your budget will help you to make a practical yet cost-effective decision. Finally, consider the room aesthetics. Curtains are a part of the overall room décor so they should complement the existing design scheme all while fulfilling your blackout or thermal needs.