Figure 1. Curtains over a window.[1]

Curtains are coverings for windows that are placed inside a home and are used to block light or thermal radiation from entering the home by covering the interior pane of the window. Curtains are generally cloth and are made of fabrics of differing opacity depending on how much light is to be blocked. Windows have a significant impact on the aesthetics and function of a building, however at times they do not function as well as people would like on their owns. The proper choice, installation, and use of window coverings such as insulated curtains or blinds can help windows keep out the cold or heat while also contributing to the appearance of the window itself.

Generally speaking, in order to get the most out of windows they need to be adjustable to the conditions that exist during different times of the day or in different seasons. Being able to adjust the window itself can prove helpful, but the addition of curtains allows a homeowner to control how much light, fresh air, and heat is allowed inside the home.[2] In addition, curtains can keep out things such as thermal radiation while also providing some degree of privacy.

Types of Curtains

There are numerous different types of curtains or window coverings that can be used in a home, and each provide different benefits. For a diagram illustrating the benefits and drawbacks of each window covering method, both internal and external, see this page. Some of the major types of window coverings are:[3]

  • Traditional Curtains: Panels of cloth fabric that are hung in front of a window on the interior side. These are generally an inexpensive, easy to install window covering option increases privacy and provides a fair amount of freedom to control light and heat. However, their insulating effects are not as dramatic as other options.
  • Insulated Cellular Shades: Pleated fabric coverings that create honeycomb-shaped cellular compartments. These compartments, which can be purchased with varying numbers of layers, trap air and provide insulation. Cellular shades also come in a wide range of opacities from sheer, light-filtering options to opaque blackout shades.[4] This option significantly increases the insulation levels of a window while providing significant amounts of control over light entrance to the home and increase privacy. However, they are significantly more expensive and difficult to install. They are also not an optimal choice for cold, wet environments as they promote condensation more than traditional curtains.[2]
  • Window Quilts: Quilted blinds are composed of a large quilt that rolls up at the top of the window and covers the entire window by a flat, thick piece of fabric when rolled down. The vertical edges of these blinds fit into channels on the side of the window to provide a better seal, and the bottom has foam or felt gasketing to ensure a tighter seal. Less expensive options can also be connected to the window by Velcro or snaps that attach the curtain to the window trim. The tight seal dramatically insulates windows while minimizing cold drafts. However, they can be more expensive and some feel that they have an objectionable appearance.[5]

To help decide which window covering works best for you, see Efficient Window Covering's personalized recommendation.

For Further Reading


  1. "Fenetre chambre" Licensed under CC BY 3.0 via Wikimedia Commons -
  2. 2.0 2.1 Megan E Phelps. (April 25, 2015). Find the Best Energy-Efficient Window Treatments [Online]. Available:
  3. Mother Earth News. (April 25, 2015). Retrofit Options [Online]. Available:
  4. The Home Depot. (April 25, 2015). Cellular Shades [Online]. Available:
  5. Efficient Window Coverings. (April 25, 2015). Window Quilt [Online]. Available:

Authors and Editors

Bethel Afework, Jordan Hanania, Kailyn Stenhouse, Jason Donev
Last updated: June 4, 2018
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