Greased paper window

A greased paper window is a very inexpensive window made of paper coated in grease. The grease fills gaps between the paper fibers, reducing the amount of light lost to scattering. Greased paper windows provide a diffuse light source, while blocking wind and preventing insects and other small animals from entering a structure.

Greased paper windows were often used by American pioneers of the early 1800s and other itinerant peoples, in lieu of relatively expensive traditional glass windows.Laura Ingalls Wilder recalled living in a home with a greased paper window in her 1937 children's novel, On the Banks of Plum Creek.

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