plastic for greenhouse

Okay, I am new here and I have a question. I put up 6 ply plastic over my hoops for the greenhouse in earlier this year. Now I have a tear across the center and instead of taking the other piece off, I added one over top, so my question is; is this going to effect the budding by not letting the amount of rays in because it is now 12 ply??? Maybe someone has used 12 ply before and it worked? Not sure, but if someone can help with an answer it would be greatly appreciated. Thank you, Seven

Are you using regular plastic sheeting or greenhouse covering material? If it's just plastic sheeting the light transmission is wrong and you plants will not grow properly. Is it opaque or clear if it's opaque then a double layer will block twice as much light.