What color are the windows tinted?
I can't answer your question definitively, but I do know that the spectrum of color in a light source will affect a plant's growth. I've only dealt with this whole issue when buying plant lights for starting seeds indoors, but it DOES make a difference!

I would make some cold frames for the spring and see how the plants do. If they do well then make yourself the greenhouse. Kim

Yes, put a few of the windows over a wooden frame of 2"x4" and see how the seedlings do. If they seem bleached out and stringy, the windows have a tint that is blocking out what the plants need a tad too much. Even so, if you need windows on the northside of the greenhouse, tinted work fine, but most folks insulate the northside during the winter. Tinted windows are better for a storage shed where you want to keep the sun UV rays off stuff to limit fading. Want to send some to me? LOL.