- 1). Seal any gaps. Use an adhesive rubber sealer or traditional caulk and seal closely around the windows and other places where air could enter the RV. Have a helper stand outside the window with a fan or hair dryer to help you find the gaps.
- 2). Apply a plastic insulation sheet to each window. There are all-in-one kits available that include tape to secure the plastic sheets over the inside of the window. Use a hair dryer to shrink the plastic, creating a tight, transparent insulation.
- 3). Use a heavy curtain as a final layer of protection against the cold. Along with warmth, this will add a cozy look to your RV's interior during the colder months.
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