lightproofing window

i have a pretty big window, 3'x6', and i need to make it completely lightproof. im planning on using black and white poly and plywood, and my main question is should i put up the poly or the plywood first? if anyone knows which way would be better thank you in advance.

You definately don't need to use 3x6 feet of plywood just to make a window lightproof. Perhaps you have plans for the wood beyond just lightproofing? When we black out windows, I'll cover it first with black construction paper and then HD foil, using black masking tape. Looks like a dark room from the outside. A little testing and patching leaks and it's gtg. If you buy some of the wider masking tape, like 2", you can cut 1-1.5" wide strips of foil, attach them down the middle of the 2" tape so there's 1/4-1/2" of tape sticking out on each side and you have light blocking tape. This stuff works well for sealing edges and seams.

well i already have the wood and the poly, but the poly by itself still lets some light through so i figured a combo of the both would work.

Go with the plywood...dont fuck around with construction paper and foil. Just be sure to use curtains or something so that you dont see the plywood over the window from the outside. Wanna make it look natural.

Use the poly on the inside....

yea sweet i was thinkin that was the better way, thanks

I would tape centerfolds from high times to the window. Then put the plywood up!!

I've always been a big fan of blackout material (can get it from any fabric store). It's white, and light tight.

Curtains then plywood are what I used with the same size window. The plywood also makes for a good sound barrier if your seal it well with caulking.

good luck