Poster board as mylar, anything wrong?

[nine33]

Hi, I've got 1000watt hps setup going, and I have hardwood floors, off white walls, and was thinking about lining the whole closet with white poster board, how well would this work in comparison to mylar? The stuff is SO expensive around my area that it's just not worth it, and I don't want to order it online.

It's 1$ per foot, unfortunately the minimum buy is 100 feet.

 

[jimmy130380]

yep it will work or you could just paint the room white

 

[fat sam]

it gives just the same effect as white paint but without the headache, mess and cost not to mention that if you rent its not always wise to paint the closet or whatever, but yeah it reflects as good as white paint, you have to be carefull though not to get it wet at all as it will discolor and i would change it out at least every crop so you dont get any weird mold or some shit growing behind it, other than that go for it, i have used it in the past and am using it now in my clone room

 

[DaveTheNewbie]

my opinion only : i think people panic too much about how reflective thier walls are.
light degrades as it travels thru air. but the time it goes to a wall, bounces (light loss here) and travels back, its nowhere near as strong anyway
if your worried about mold, paint your poster board in mold resistant white paint
look at pro commercial grows, there isnt any mylar there

 

[nine33]

Yeah I haven't been concerned about reflectivity until today when I got my window ac unit in and got temps under control. Just looking to tweak my room as much as possible now to maximize the yield. Though with 1000watts inside of a 3x3 area, I don't really know if it matters that much, I was just mainly concerned about the undergrowth and bottom leaves, the walls are white, but the floors aren't.

Thanks for clearing this up.

 

[GoldenGanja13]

I went to Home depot and paid 14$ for a 9x4 piece of foam board that was insulated on one side. Works great for my veg room.

 

[jimmy130380]

put some 3ft fluro down low and that should help the under growth but those sun shild car mats work great and there like 2 bucks for 5 of em but you got a ac ,1000watter why not just go the 9 yards

 

[syze]

you are 100% correct but still, it is more then the plant would recieve if it wouldnt bounce back? or am i mistaken?

my opinion only : i think people panic too much about how reflective thier walls are.
light degrades as it travels thru air. but the time it goes to a wall, bounces (light loss here) and travels back, its nowhere near as strong anyway
if your worried about mold, paint your poster board in mold resistant white paint
look at pro commercial grows, there isnt any mylar there

 

[syze]

Yeah I haven't been concerned about reflectivity until today when I got my window ac unit in and got temps under control. Just looking to tweak my room as much as possible now to maximize the yield. Though with 1000watts inside of a 3x3 area, I don't really know if it matters that much, I was just mainly concerned about the undergrowth and bottom leaves, the walls are white, but the floors aren't.

Thanks for clearing this up.

my advice to you is do not put any reflective material on the ground or anywere to reflect light up under neath the plant, the undersides of the leaves are used by the stomata to cntrol the moisture/breathing of the plant, not ment to absorb light, so i would advize against putting a reflective material on the bottom. And with a 1000w lamp you should be penetrating that underneath foliage or do you have it incredibly dense under the light? hope all works well for you, thumbs up -syze-