Vinyl Window Insulating Materials

Plastic

• Properly applied plastic insulates vinyl windows. Inexpensive window insulation kits include plastic shrink wrap and double-stick adhesive strips; the plastic is cut to the size needed for the entire interior window frame. The plastic covers the interior window frame, secured by the strips. Once the plastic is taped down, you use a hair dryer to heat the plastic, which removes wrinkles and creates a clinging effect. Although the plastic does insulate vinyl windows effectively, it's noticeable and gives the window glass a "cloudy" or "film" appearance.

Rubber

• Rubber is a common weather sealant material used on vinyl windows, often sold as rolled, self-sticking strips. You cut two rubber strips to the size of the window frame's height and place a strip in the space between the frame and the wall to close any gaps; the remaining strip goes on the other side of the window frame. While inexpensive, the strips may fail to stick to the vinyl window properly or leave an adhesive residue once removed. Vinyl windows don't need paint, so unlike with wooden windows, damaged paint from adhesive removal isn't a problem.

Fabric

• Curtains made of heavy fabrics, such as polyester and cotton, or layers of fabric curtains insulate a vinyl window while adding to the home's decor. Heavier interior curtains will block out sunlight to the room. Layering a set of two panel curtains — for example, using two thin, light curtain panels on the vinyl window underneath two heavier fabric panels — lets you increase sunlight to the room easily while maintaining privacy. Curtains may be used to "hide" or accent vinyl windows, but if you choose to accent the window, consider the color of the vinyl when selecting insulating curtains. While white is common, vinyl windows come in various colors, including shades of red and green.

Spray Forms (Water or Latex)

• Vinyl windows expand and contract because of cold and heat. Cracks, gaps and holes around the frame because of expansion and contraction allow heat and cool air to escape. Non-expanding spray foams come in water- and latex-based compounds and may be used to seal vinyl window cracks and small or medium gaps. Expanding foams should never be used to insulate a vinyl window; the expansion damages the window frame. Water-based foams are often messier to work with than latex-based foams but don't produce greenhouse gases. Non-expanding spray foam needs around 24 hours to dry and will not cure correctly in large spaces because of reduced air exposure.