The older your windows, the more the curtains will be moving. Trim at the top and bottom may be past its prime. The frame may be rotted or rusted, creating an uneven surface for the window to rest in. These gaps will allow wind to work its way into your home.
Sure…the stop gap of the old plastic over the windows kits at home stores can help…a bit. But, if you’re at that point – you might want to consider replacing them.
Replacement windows are top notch. Vinyl – no maintenance. Double paned insulated argon filled glass. Many come with UV coatings to keep your curtains from fading. Therma Tru is the way to go.
Top notch brands like Harvey, Simonton, Certainteed, Pella, and Andersen windows all carry the Energy Star rating. Three cheers for energy efficiency - they are all quality products with warrantees that will last for years. Keep your curtains hanging as they should, for privacy and décor - making you a happy camper when your energy bills begin to decrease.