Our collection of blackout curtains will ensure the whole family can get an uninterrupted night's sleep. Whether you are looking to block out the late evening sun or the streetlights on your busy road, our blackout curtains come in a range of styles and colours all designed to keep the light out. How Do Thermal Curtains Work? The principle behind thermal curtains is the same one that inspires insulation. With multiple layers, air and heat cannot readily pass through the curtain barrier. This creates a dead-air space. This dead space reduces the amount of air that moves through the room. It also reduces the transfer of heat. In other words, when it is hot outside, that heat penetrates the room less. When it is cold outside, warm air is more likely to stay inside. This means that the thermal properties allow for easier temperature regulation. The efficacy of the curtains will vary depending on the materials used and their specific R-values. If you want to see how well your curtains will perform, look closely at the R-value of the curtain. Higher values are going to provide a more pronounced insulating effect. When a quality thermal curtain is used, it can definitely help slow the loss of air, heat and sound from the space.