White Blackout Curtains

I'm making curtains and keep them in line with blackout lining. Can I use a flat white sheet instead of the blackout lining? I would like to completely block the sun's rays and keep the heat or AC inside. In addition, the sun will make them change color or will it stay white?

White sheets do not give you a total ban. You do not have to go with something darker and yes, the sun will fade over time.

Yes, always assuming that you do not have white curtains. course.

White bed sheets? No! Do not go to work for the result you are looking for ...