White Paint vs. Aluminum Foil For Reflectivity

[NIMBY]

I noticed a thread about whether white painted walls are better for reflection than aluminum foil. I haven't been keeping up with these types of forums for quite a few years but I would have thought that it's a settled issue by now. It's so easy to prove!

Aluminum foil is the winner, hands down!

I have a cheapy light meter and will snap some pix in a while. If anyone else has a meter, just step out and reflect the sun off a piece of foil and off something that's painted white. Try bright white and flat white and both sides of the foil. Let's settle this once and for all.

In the old days they even said that when using foil, the dull side was better. Wrong again. As far as simple reflectivity, the shiny side of the foil will reflect nearly all the light.

Some of the arguments had to do with causing something like the effect from a magnifying glass. Somehow more light would be focused at a leaf or something and it would cause a burn. I've tried everything I could with the bright side of the foil to get it to reflect MORE light than goes in and it's just not happening. When all is said and done, it's not a magnifying glass.

Comments or thoughts? I'll post some photos later. Happy 420 everyone!

 

[Puscifer]

I'll take Orca over paint, foil or panda film... Expensive and worth every penny!

 

[Hydro-Soil]

Foil creases easily, distorting the reflection. Tarnishes after a while and is easily torn.
It's also highly conductive.

Flat white paint is cheap, easy to apply, provides an even reflection of light and is SUPER easy to clean. Gets too dinged, slap on another coat of paint, probably 2 or 3 left in the original can.

Foil more reflective? Yep. Pain in the ass to use? Yep. Worth it to just go with flat white paint in the long run? YEP.

Stay Safe!

p.s. Yes, it does burn leaves. No, it doesn't 'magnify' the light but creases and wrinkles will reflect multiple sources from it onto the same leaf, thereby concentrating the light. HID and foil is pretty much a no-no for optimal growing.

 

[RM - aquagrower]

Big fan of reflectix here. Cover everything that ain't green.

I do remember this discussion from OG. Back then it was said to use the dull side of foil. Tried it. What a pain. Found reflectix at home depot and never looked back.

Nice to see ya NIMBY.

 

[Mud Boy]

You can get hot spots with stuff like foil and mylar and seems to me that white paint would reflect the full spectrum. I wonder how aluminum roof paint would work? It's flat but it reflects heat well. Not sure about light.

 

[oscar169]

Here is a good paint to use, made for high RH rooms, bath rooms, no mold, or mildew.

 

[irishdude5186]

Has anyone done a test with light meters? It should be an easy test right? People would get over the pain of foil versus paint if there was a real tangible benefit from mylar/orca/foil

 

[trichster]

foil is for the kitchen! Use white paint if your going the easy cheap route. Mylar is definitly more reflective then white paint. Put your hand between wall covered in mylar/white paint and your plants and you will see a major difference in reflectiveness. Id say white paint is 75% reflective where as mylar is 95%.

 

[irishdude5186]

foil is for the kitchen! Use white paint if your going the easy cheap route. Mylar is definitly more reflective then white paint. Put your hand between wall covered in mylar/white paint and your plants and you will see a major difference in reflectiveness. Id say white paint is 75% reflective where as mylar is 95%.

Thanks for the input, but it still would be nice if someone has done a test with a light meter to put all this to bed with certainty..

 

[foomar]

Under a microscope at 400x mylar is still smooth and reflects an image , white paint looks like a pile of white rubble and reflects nearly as well but is so diffused as to be difficult to compare and measure.

Have used both and now stick with a quality white vinyl silk emulsion , cleaning mylar of spray residue leads to tearing and the glue or tape fixing it eventually fails , and dirty mylar is no better than white paint.

I add a good dose of Dithane fungicide and stir it in well , wipes clean and stops mould as good as the more expensive specialised paints sold with a fungicide already in there.

 

[RM - aquagrower]

Thanks for the input, but it still would be nice if someone has done a test with a light meter to put all this to bed with certainty..

It's been done. Aluminum foil wasn't tested IIRC. You'll just have to search a bit.

The results were: orca>mylar>reflectix>white paint

I chose the reflectix because, first, I can get it at home depot. Next, It's easily reusable (I install it w/ 5/16 "slap staples"). Next, it adds a bit of R-value (helps with DIF). And lastly, adds a bit of soundproofing to help cover fan noise.

Ultimately, it's a decision that each grower must make to fit their personal situation.

 

[RB56]

I use rolls of aluminum flashing. It's between the shiny and dull side of foil in reflectivity, is very durable, easily cleanable and adds some fireproofing to the room.

 

[Vokuhila]

Theres some tests in Cervantes book "Indoor Marihuana Horticulture"; http://books.google.de/books?id=rnw...epage&q=cervantes reflective aluminum&f=false
White paint ist what i have always used, doesn't seem like a bad choice, though thats partly because i'm just too lazy to glue aluminum foil to the walls.

 

[oscar169]

Just paint the walls white,paint the floor white, make it all white, It will hurt your eyes with no plants in the room, b/c it will be soo bright & if not then just add more lights/watts

 

[sabaean]

Best of both worlds

Best of both worlds

http://www.eaglecoatings.net/content/sunshield2000.htm

I use this over ceili[FONT=&quot][FONT=&quot]n[/FONT]g, walls, floor. It also has the added benefit[/FONT][FONT=&quot][FONT=&quot] of thwarti[/FONT][/FONT][FONT=&quot][FONT=&quot][FONT=&quot][FONT=&quot]n[/FONT]g helo's flir cams.[/FONT][/FONT] [/FONT]

 

[Granger2]

> The results were: orca>mylar>reflectix>white paint

I read a book about 25 years ago called "The Facts of Light." Flat white reflects about 90%. All the other available reflective films like mylar, foil, Orca, etc. relect a few more %, but the difference will translate to virtually no change in plant yield. We're talking about a very small portion of the light that comes out of your lamp.

White totally diffuses the light it reflects. This scattering gives the illusion that it isn't reflecting as well as a mirrored surface.

Just finished my room make over. No more mylar. White paint is so much easier to install, clean, repair, etc. It doesn't come loose. Nice looking too. Good luck. -granger