Do drapes and window shades cause window condensation? No, but drapes and other window coverings can restrict the flow of warm room air over glass surfaces. Therefore, condensation is more likely to occur when drapes are closed and shades are pulled down.

Do curtains prevent condensation?

You're probably wondering how curtains can possibly effect condensation. They trap heat against your windows forcing warmer temperatures to meet the freezing cold temperatures outside. You've already learned that reducing the temperature inside can help with condensation.

Can heavy curtains cause condensation?

(10) Condensation can be caused by isolating the inner glass from the warm room air with heavy curtains when drawn.