One of the best energy efficient features a home can have is insulated windows. They help keep a temperature indoors comfortable, but it’s not uncommon to see these windows sweating during temperature extremes.
If condensation forms on the outside of your window, that’s a good thing. It means the window is doing its job. But if condensation forms on the inside, you have a problem. It usually means outside air is somehow migrating inside or humidity levels inside are just too high.
To help combat this moisture, seal any gaps and cracks surrounding the insulated window using a good quality acrylic latex caulk. Be sure to use ventilation fans in bathrooms and kitchens. And, if needed, use a dehumidifier to lower indoor humidity. The ideal range you want inside is between 35% and 50%.