Emergency Blankets

Does anyone know if lining the walls of your grow space with an emergency blanket (the reflective kind) is a good source of reflection so more light gets to the plants?

most emergency blankets I've seen are semi-transparent so I couldn't recommend it.

Go buy those cheap-ass mylar things you use to cover the inside of your windshield when it's hot outside. They work very well.

nah emergency blankets are the greatest thing, they are really reflective. i use them and for 3 bucks at walmart you get a huge huge sheet of it. it is sort of transparent but when you tape it up it it isnt. i highly recommend it as a replacement if u cant afford mylar and want to use something way better then tin foil.

it depends on where the mylar blankets come from, some of them have a very reflective side and a slightly less reflective side. The best result with them... because as stated they are semitransparent... is to attach them flat to something with a dark color for the backing. I use cardboard for it because the cardboard panels are light and easy to adjust as the plant grows. (I lucked out though, I had a couple of ridiculously large cardboard boxes on hand)
It's not the ideal reflective surface but it's light easily cut and folded and probably a little easier to get a hold of. I got mine in a pack of 10 for just a few bucks. it was enough to paste the entire closet I still have 7 of them unused and threw away pretty big parts of the 3 I did use that were cut up a little.

The problem is also the color of the emergency blanket. Reflection works by subtractive blending so if it's a yellow blanket you're really only getting mostly yellow reflected, not red and blue like you'd want. If you find the silvered ones they work best against a bright white flat surface, not a dark surface, for the same reasons.

Yeah you want to put the blankets over a White colored surface, not a black one as was suggested. This may seem counter intuitive but believe me that black will absorb light, and white will reflect it, after all you aren't changing the actual reflectivity, just the appearance of it, light still gets through somewhat and white will reflect much more of it back out. Not to mention the heat absorption that black has, just might cause problems.